Appendix E: Built-in Template

Chapter 4 lists a number of the most useful built-in template tags and filters. However, Django ships with many more built-in tags and filters. This appendix covers them.

Built-in Tag Reference

autoescape

Controls the current auto-escaping behavior. This tag takes either on or off as an argument and that determines whether auto-escaping is in effect inside the block. The block is closed with an endautoescapeending tag.

When auto-escaping is in effect, all variable content has HTML escaping applied to it before placing the result into the output (but after any filters have been applied). This is equivalent to manually applying the escape filter to each variable.

The only exceptions are variables that are already marked as safe from escaping, either by the code that populated the variable, or because it has had the safe or escape filters applied.

Sample usage:

{% autoescape on %}
    {{ body }}
{% endautoescape %}

block

Defines a block that can be overridden by child templates. See Template inheritance for more information.

comment

Ignores everything between {% comment %} and {% endcomment %}. An optional note may be inserted in the first tag. For example, this is useful when commenting out code for documenting why the code was disabled.

Sample usage:

<p>Rendered text with {{ pub_date|date:"c" }}</p>
{% comment "Optional note" %}
    <p>Commented out text with {{ create_date|date:"c" }}</p>
{% endcomment %}

comment tags cannot be nested.

csrf_token

This tag is used for CSRF protection, as described in the documentation for Cross Site Request Forgeries .

cycle

Produces one of its arguments each time this tag is encountered. The first argument is produced on the first encounter, the second argument on the second encounter, and so forth. Once all arguments are exhausted, the tag cycles to the first argument and produces it again.

This tag is particularly useful in a loop:

{% for o in some_list %}
    <tr class="{% cycle "row1" "row2" %}">
        ...
    </tr>
{% endfor %}

The first iteration produces HTML that refers to class row1, the second to row2, the third to row1 again, and so on for each iteration of the loop.

You can use variables, too. For example, if you have two template variables, rowvalue1 and rowvalue2, you can alternate between their values like this:

{% for o in some_list %}
    <tr class="{% cycle rowvalue1 rowvalue2 %}">
        ...
    </tr>
{% endfor %}

Variables included in the cycle will be escaped. You can disable auto-escaping with:

{% for o in some_list %}
    <tr class="{% autoescape off %}{% cycle rowvalue1 rowvalue2 %}{% endautoescape %}">
        ...
    </tr>
{% endfor %}

You can mix variables and strings:

{% for o in some_list %}
    <tr class="{% cycle "row1" rowvalue2 "row3" %}">
        ...
    </tr>
{% endfor %}

In some cases you might want to refer to the current value of a cycle without advancing to the next value. To do this, just give the {% cycle %} tag a name, using as, like this:

{% cycle "row1" "row2" as rowcolors %}

From then on, you can insert the current value of the cycle wherever youd like in your template by referencing the cycle name as a context variable. If you want to move the cycle to the next value independently of the original cycle tag, you can use another cycle tag and specify the name of the variable. So, the following template:

<tr>
    <td class="{% cycle "row1" "row2" as rowcolors %}">...</td>
    <td class="{{ rowcolors }}">...</td>
</tr>
<tr>
    <td class="{% cycle rowcolors %}">...</td>
    <td class="{{ rowcolors }}">...</td>
</tr>

would output:

<tr>
    <td class="row1">...</td>
    <td class="row1">...</td>
</tr>
<tr>
    <td class="row2">...</td>
    <td class="row2">...</td>
</tr>

You can use any number of values in a cycle tag, separated by spaces. Values enclosed in single quotes (") or double quotes (") are treated as string literals, while values without quotes are treated as template variables.

By default, when you use the as keyword with the cycle tag, the usage of {% cycle %} that initiates the cycle will itself produce the first value in the cycle. This could be a problem if you want to use the value in a nested loop or an included template. If you only want to declare the cycle but not produce the first value, you can add a silent keyword as the last keyword in the tag. For example:

{% for obj in some_list %}
    {% cycle "row1" "row2" as rowcolors silent %}
    <tr class="{{ rowcolors }}">{% include "subtemplate.html" %}</tr>
{% endfor %}

This will output a list of <tr> elements with class alternating between row1 and row2. The subtemplate will have access to rowcolors in its context and the value will match the class of the <tr> that encloses it. If thesilent keyword were to be omitted, row1 and row2 would be emitted as normal text, outside the <tr>element.

When the silent keyword is used on a cycle definition, the silence automatically applies to all subsequent uses of that specific cycle tag. The following template would output nothing, even though the second call to {% cycle %} doesnt specify silent:

{% cycle "row1" "row2" as rowcolors silent %}
{% cycle rowcolors %}

For backward compatibility, the {% cycle %} tag supports the much inferior old syntax from previous Django versions. You shouldnt use this in any new projects, but for the sake of the people who are still using it, heres what it looks like:

{% cycle row1,row2,row3 %}

In this syntax, each value gets interpreted as a literal string, and theres no way to specify variable values. Or literal commas. Or spaces. Did we mention you shouldnt use this syntax in any new projects?

debug

Outputs a whole load of debugging information, including the current context and imported modules.

extends

Signals that this template extends a parent template.

This tag can be used in two ways:

• {% extends "base.html" %} (with quotes) uses the literal value "base.html" as the name of the parent template to extend.
• {% extends variable %} uses the value of variable. If the variable evaluates to a string, Django will use that string as the name of the parent template. If the variable evaluates to a Template object, Django will use that object as the parent template.

See template-inheritance for more information.

filter

Filters the contents of the block through one or more filters. Multiple filters can be specified with pipes and filters can have arguments, just as in variable syntax.

Note that the block includes all the text between the filter and endfilter tags.

Sample usage:

{% filter force_escape|lower %}
    This text will be HTML-escaped, and will appear in all lowercase.
{% endfilter %}

Note

The escape and safe filters are not acceptable arguments. Instead, use the autoescape tag to manage autoescaping for blocks of template code.

firstof

Outputs the first argument variable that is not False. Outputs nothing if all the passed variables are False.

Sample usage:

{% firstof var1 var2 var3 %}

This is equivalent to:

{% if var1 %}
    {{ var1 }}
{% elif var2 %}
    {{ var2 }}
{% elif var3 %}
    {{ var3 }}
{% endif %}

You can also use a literal string as a fallback value in case all passed variables are False:

{% firstof var1 var2 var3 "fallback value" %}

This tag auto-escapes variable values. You can disable auto-escaping with:

{% autoescape off %}
    {% firstof var1 var2 var3 "<strong>fallback value</strong>" %}
{% endautoescape %}

Or if only some variables should be escaped, you can use:

{% firstof var1 var2|safe var3 "<strong>fallback value</strong>"|safe %}

for

Loops over each item in an array, making the item available in a context variable. For example, to display a list of athletes provided in athlete_list:

<ul>
{% for athlete in athlete_list %}
    <li>{{ athlete.name }}</li>
{% endfor %}
</ul>

You can loop over a list in reverse by using {% for obj in list reversed %}.

If you need to loop over a list of lists, you can unpack the values in each sublist into individual variables. For example, if your context contains a list of (x,y) coordinates called points, you could use the following to output the list of points:

{% for x, y in points %}
    There is a point at {{ x }},{{ y }}
{% endfor %}

This can also be useful if you need to access the items in a dictionary. For example, if your context contained a dictionary data, the following would display the keys and values of the dictionary:

{% for key, value in data.items %}
    {{ key }}: {{ value }}
{% endfor %}

The for loop sets a number of variables available within the loop:

Variable	Description
forloop.counter	The current iteration of the loop (1-indexed)
forloop.counter0	The current iteration of the loop (0-indexed)
forloop.revcounter	The number of iterations from the end of the loop (1-indexed)
forloop.revcounter0	The number of iterations from the end of the loop (0-indexed)
forloop.first	True if this is the first time through the loop
forloop.last	True if this is the last time through the loop
forloop.parentloop	For nested loops, this is the loop surrounding the current one

for … empty

The for tag can take an optional {% empty %} clause whose text is displayed if the given array is empty or could not be found:

<ul>
{% for athlete in athlete_list %}
    <li>{{ athlete.name }}</li>
{% empty %}
    <li>Sorry, no athletes in this list.</li>
{% endfor %}
</ul>

The above is equivalent to but shorter, cleaner, and possibly faster than the following:

<ul>
  {% if athlete_list %}
    {% for athlete in athlete_list %}
      <li>{{ athlete.name }}</li>
    {% endfor %}
  {% else %}
    <li>Sorry, no athletes in this list.</li>
  {% endif %}
</ul>

if

The {% if %} tag evaluates a variable, and if that variable is true (i.e. exists, is not empty, and is not a false boolean value) the contents of the block are output:

{% if athlete_list %}
    Number of athletes: {{ athlete_list|length }}
{% elif athlete_in_locker_room_list %}
    Athletes should be out of the locker room soon!
{% else %}
    No athletes.
{% endif %}

In the above, if athlete_list is not empty, the number of athletes will be displayed by the {{athlete_list|length }} variable.

As you can see, the if tag may take one or several {% elif %} clauses, as well as an {% else %} clause that will be displayed if all previous conditions fail. These clauses are optional.

Boolean operators

if tags may use and, or or not to test a number of variables or to negate a given variable:

{% if athlete_list and coach_list %}
    Both athletes and coaches are available.
{% endif %}

{% if not athlete_list %}
    There are no athletes.
{% endif %}

{% if athlete_list or coach_list %}
    There are some athletes or some coaches.
{% endif %}

{% if not athlete_list or coach_list %}
    There are no athletes or there are some coaches.
{% endif %}

{% if athlete_list and not coach_list %}
    There are some athletes and absolutely no coaches.
{% endif %}

Use of both and and or clauses within the same tag is allowed, with and having higher precedence than ore.g.:

{% if athlete_list and coach_list or cheerleader_list %}

will be interpreted like:

if (athlete_list and coach_list) or cheerleader_list

Use of actual parentheses in the if tag is invalid syntax. If you need them to indicate precedence, you should use nested if tags.

if tags may also use the operators ==, !=, <, >, <=, >= and in which work as follows:

== operator

Equality. Example:

{% if somevar == "x" %}
  This appears if variable somevar equals the string "x"
{% endif %}

!= operator

Inequality. Example:

{% if somevar != "x" %}
  This appears if variable somevar does not equal the string "x",
  or if somevar is not found in the context
{% endif %}

< operator

Less than. Example:

{% if somevar < 100 %}
  This appears if variable somevar is less than 100.
{% endif %}

> operator

Greater than. Example:

{% if somevar > 0 %}
  This appears if variable somevar is greater than 0.
{% endif %}

<= operator

Less than or equal to. Example:

{% if somevar <= 100 %}
  This appears if variable somevar is less than 100 or equal to 100.
{% endif %}

>= operator

Greater than or equal to. Example:

{% if somevar >= 1 %}
  This appears if variable somevar is greater than 1 or equal to 1.
{% endif %}

in operator

Contained within. This operator is supported by many Python containers to test whether the given value is in the container. The following are some examples of how x in y will be interpreted:

{% if "bc" in "abcdef" %}
  This appears since "bc" is a substring of "abcdef"
{% endif %}

{% if "hello" in greetings %}
  If greetings is a list or set, one element of which is the string
  "hello", this will appear.
{% endif %}

{% if user in users %}
  If users is a QuerySet, this will appear if user is an
  instance that belongs to the QuerySet.
{% endif %}

not in operator

Not contained within. This is the negation of the in operator.

The comparison operators cannot be chained like in Python or in mathematical notation. For example, instead of using:

{% if a > b > c %}  (WRONG)

you should use:

{% if a > b and b > c %}

Filters

You can also use filters in the if expression. For example:

{% if messages|length >= 100 %}
   You have lots of messages today!
{% endif %}

Complex expressions

All of the above can be combined to form complex expressions. For such expressions, it can be important to know how the operators are grouped when the expression is evaluated – that is, the precedence rules. The precedence of the operators, from lowest to highest, is as follows:

• or
• and
• not
• in
• ==, !=, <, >, <=, >=

(This follows Python exactly). So, for example, the following complex if tag:

{% if a == b or c == d and e %}

…will be interpreted as:

(a == b) or ((c == d) and e)

If you need different precedence, you will need to use nested if tags. Sometimes that is better for clarity anyway, for the sake of those who do not know the precedence rules.

ifchanged

Check if a value has changed from the last iteration of a loop.

The {% ifchanged %} block tag is used within a loop. It has two possible uses.

1. Checks its own rendered contents against its previous state and only displays the content if it has changed. For example, this displays a list of days, only displaying the month if it changes:

   <h1>Archive for {{ year }}</h1>
   
   {% for date in days %}
       {% ifchanged %}<h3>{{ date|date:"F" }}</h3>{% endifchanged %}
       <a href="{{ date|date:"M/d"|lower }}/">{{ date|date:"j" }}</a>
   {% endfor %}
   

2. If given one or more variables, check whether any variable has changed. For example, the following shows the date every time it changes, while showing the hour if either the hour or the date has changed:

   {% for date in days %}
       {% ifchanged date.date %} {{ date.date }} {% endifchanged %}
       {% ifchanged date.hour date.date %}
           {{ date.hour }}
       {% endifchanged %}
   {% endfor %}
   

The ifchanged tag can also take an optional {% else %} clause that will be displayed if the value has not changed:

{% for match in matches %}
    <div style="background-color:
        {% ifchanged match.ballot_id %}
            {% cycle "red" "blue" %}
        {% else %}
            gray
        {% endifchanged %}
    ">{{ match }}</div>
{% endfor %}

ifequal

Output the contents of the block if the two arguments equal each other.

Example:

{% ifequal user.pk comment.user_id %}
    ...
{% endifequal %}

As in the if tag, an {% else %} clause is optional.

The arguments can be hard-coded strings, so the following is valid:

{% ifequal user.username "adrian" %}
    ...
{% endifequal %}

An alternative to the ifequal tag is to use the if tag and the == operator.

ifnotequal

Just like ifequal, except it tests that the two arguments are not equal.

An alternative to the ifnotequal tag is to use the if tag and the != operator.

include

Loads a template and renders it with the current context. This is a way of including other templates within a template.

The template name can either be a variable or a hard-coded (quoted) string, in either single or double quotes.

This example includes the contents of the template "foo/bar.html":

{% include "foo/bar.html" %}

This example includes the contents of the template whose name is contained in the variabletemplate_name:

{% include template_name %}

The variable may also be any object with a render() method that accepts a context. This allows you to reference a compiled Template in your context.

An included template is rendered within the context of the template that includes it. This example produces the output "Hello, John":

• Context: variable person is set to "john".

• Template:

  {% include "name_snippet.html" %}
  

• The name_snippet.html template:

  {{ greeting }}, {{ person|default:"friend" }}!
  

You can pass additional context to the template using keyword arguments:

{% include "name_snippet.html" with person="Jane" greeting="Hello" %}

If you want to render the context only with the variables provided (or even no variables at all), use theonly option. No other variables are available to the included template:

{% include "name_snippet.html" with greeting="Hi" only %}

Note

The include tag should be considered as an implementation of render this subtemplate and include the HTML, not as parse this subtemplate and include its contents as if it were part of the parent. This means that there is no shared state between included templates each include is a completely independent rendering process.

Blocks are evaluated before they are included. This means that a template that includes blocks from another will contain blocks that have already been evaluated and rendered – not blocks that can be overridden by, for example, an extending template.

load

Loads a custom template tag set.

For example, the following template would load all the tags and filters registered in somelibrary andotherlibrary located in package package:

{% load somelibrary package.otherlibrary %}

You can also selectively load individual filters or tags from a library, using the from argument. In this example, the template tags/filters named foo and bar will be loaded from somelibrary:

{% load foo bar from somelibrary %}

See Custom tag and filter libraries for more information.

lorem

Displays random lorem ipsum Latin text. This is useful for providing sample data in templates.

Usage:

{% lorem [count] [method] [random] %}

The {% lorem %} tag can be used with zero, one, two or three arguments. The arguments are:

Argument	Description
count	A number (or variable) containing the number of paragraphs or words to generate (default is 1).
method	Either w for words, p for HTML paragraphs or b for plain-text paragraph blocks (default isb).
random	The word random, which if given, does not use the common paragraph (Lorem ipsum dolor sit amet…) when generating text.

Examples:

• {% lorem %} will output the common lorem ipsum paragraph.
• {% lorem 3 p %} will output the common lorem ipsum paragraph and two random paragraphs each wrapped in HTML <p> tags.
• {% lorem 2 w random %} will output two random Latin words.

now

Displays the current date and/or time, using a format according to the given string. Such string can contain format specifiers characters as described in the date filter section.

Example:

It is {% now "jS F Y H:i" %}

Note that you can backslash-escape a format string if you want to use the raw value. In this example, both o and f are backslash-escaped, because otherwise each is a format string that displays the year and the time, respectively:

It is the {% now "jS of F" %}

This would display as It is the 4th of September.

Note

The format passed can also be one of the predefined ones DATE_FORMAT, DATETIME_FORMAT, SHORT_DATE_FORMAT orSHORT_DATETIME_FORMAT. The predefined formats may vary depending on the current locale and if format-localization is enabled, e.g.:

It is {% now "SHORT_DATETIME_FORMAT" %}

You can also use the syntax {% now "Y" as current_year %} to store the output inside a variable. This is useful if you want to use {% now %} inside a template tag like blocktrans for example:

{% now "Y" as current_year %}
{% blocktrans %}Copyright {{ current_year }}{% endblocktrans %}

regroup

Regroups a list of alike objects by a common attribute.

This complex tag is best illustrated by way of an example: say that places is a list of cities represented by dictionaries containing "name", "population", and "country" keys:

cities = [
    {"name": "Mumbai", "population": "19,000,000", "country": "India"},
    {"name": "Calcutta", "population": "15,000,000", "country": "India"},
    {"name": "New York", "population": "20,000,000", "country": "USA"},
    {"name": "Chicago", "population": "7,000,000", "country": "USA"},
    {"name": "Tokyo", "population": "33,000,000", "country": "Japan"},
]

…and youd like to display a hierarchical list that is ordered by country, like this:

• India
  • Mumbai: 19,000,000
  • Calcutta: 15,000,000
• USA
  • New York: 20,000,000
  • Chicago: 7,000,000
• Japan
  • Tokyo: 33,000,000

You can use the {% regroup %} tag to group the list of cities by country. The following snippet of template code would accomplish this:

{% regroup cities by country as country_list %}

<ul>
{% for country in country_list %}
    <li>{{ country.grouper }}
    <ul>
        {% for item in country.list %}
          <li>{{ item.name }}: {{ item.population }}</li>
        {% endfor %}
    </ul>
    </li>
{% endfor %}
</ul>

Lets walk through this example. {% regroup %} takes three arguments: the list you want to regroup, the attribute to group by, and the name of the resulting list. Here, were regrouping the cities list by thecountry attribute and calling the result country_list.

{% regroup %} produces a list (in this case, country_list) of group objects. Each group object has two attributes:

• grouper  the item that was grouped by (e.g., the string India or Japan).
• list  a list of all items in this group (e.g., a list of all cities with country=India).

Note that {% regroup %} does not order its input! Our example relies on the fact that the cities list was ordered by country in the first place. If the cities list did not order its members by country, the regrouping would naively display more than one group for a single country. For example, say the cities list was set to this (note that the countries are not grouped together):

cities = [
    {"name": "Mumbai", "population": "19,000,000", "country": "India"},
    {"name": "New York", "population": "20,000,000", "country": "USA"},
    {"name": "Calcutta", "population": "15,000,000", "country": "India"},
    {"name": "Chicago", "population": "7,000,000", "country": "USA"},
    {"name": "Tokyo", "population": "33,000,000", "country": "Japan"},
]

With this input for cities, the example {% regroup %} template code above would result in the following output:

• India
  • Mumbai: 19,000,000
• USA
  • New York: 20,000,000
• India
  • Calcutta: 15,000,000
• USA
  • Chicago: 7,000,000
• Japan
  • Tokyo: 33,000,000

The easiest solution to this gotcha is to make sure in your view code that the data is ordered according to how you want to display it.

Another solution is to sort the data in the template using the dictsort filter, if your data is in a list of dictionaries:

{% regroup cities|dictsort:"country" by country as country_list %}

Grouping on other properties

Any valid template lookup is a legal grouping attribute for the regroup tag, including methods, attributes, dictionary keys and list items. For example, if the country field is a foreign key to a class with an attribute description, you could use:

{% regroup cities by country.description as country_list %}

Or, if country is a field with choices, it will have a get_FOO_display() method available as an attribute, allowing you to group on the display string rather than the choices key:

{% regroup cities by get_country_display as country_list %}

{{ country.grouper }} will now display the value fields from the choices set rather than the keys.

spaceless

Removes whitespace between HTML tags. This includes tab characters and newlines.

Example usage:

{% spaceless %}
    <p>
        <a href="foo/">Foo</a>
    </p>
{% endspaceless %}

This example would return this HTML:

<p><a href="foo/">Foo</a></p>

Only space between tags is removed not space between tags and text. In this example, the space aroundHello wont be stripped:

{% spaceless %}
    <strong>
        Hello
    </strong>
{% endspaceless %}

templatetag

Outputs one of the syntax characters used to compose template tags.

Since the template system has no concept of escaping, to display one of the bits used in template tags, you must use the {% templatetag %} tag.

The argument tells which template bit to output:

Argument	Outputs
openblock	{%
closeblock	%}
openvariable	{{
closevariable	}}
openbrace	{
closebrace	}
opencomment	{#
closecomment	#}

Sample usage:

{% templatetag openblock %} url "entry_list" {% templatetag closeblock %}

url

Returns an absolute path reference (a URL without the domain name) matching a given view function and optional parameters. Any special characters in the resulting path will be encoded using iri_to_uri().

This is a way to output links without violating the DRY principle by having to hard-code URLs in your templates:

{% url "some-url-name" v1 v2 %}

The first argument is a path to a view function in the format package.package.module.function. It can be a quoted literal or any other context variable. Additional arguments are optional and should be space-separated values that will be used as arguments in the URL. The example above shows passing positional arguments. Alternatively you may use keyword syntax:

{% url "some-url-name" arg1=v1 arg2=v2 %}

Do not mix both positional and keyword syntax in a single call. All arguments required by the URLconf should be present.

For example, suppose you have a view, app_views.client, whose URLconf takes a client ID (here, client() is a method inside the views file app_views.py). The URLconf line might look like this:

("^client/([0-9]+)/$", "app_views.client", name="app-views-client")

If this apps URLconf is included into the projects URLconf under a path such as this:

("^clients/", include("project_name.app_name.urls"))

…then, in a template, you can create a link to this view like this:

{% url "app-views-client" client.id %}

The template tag will output the string /clients/client/123/.

If youre using named URL patterns , you can refer to the name of the pattern in the url tag instead of using the path to the view.

Note that if the URL youre reversing doesnt exist, youll get an NoReverseMatch exception raised, which will cause your site to display an error page.

If youd like to retrieve a URL without displaying it, you can use a slightly different call:

{% url "some-url-name" arg arg2 as the_url %}

<a href="{{ the_url }}">I"m linking to {{ the_url }}</a>

The scope of the variable created by the as var syntax is the {% block %} in which the {% url %} tag appears.

This {% url ... as var %} syntax will not cause an error if the view is missing. In practice youll use this to link to views that are optional:

{% url "some-url-name" as the_url %}
{% if the_url %}
  <a href="{{ the_url }}">Link to optional stuff</a>
{% endif %}

If youd like to retrieve a namespaced URL, specify the fully qualified name:

{% url "myapp:view-name" %}

This will follow the normal namespaced URL resolution strategy , including using any hints provided by the context as to the current application.

Deprecated since version 1.8: The dotted Python path syntax is deprecated and will be removed in Django 2.0:

{% url "path.to.some_view" v1 v2 %}

Warning

Dont forget to put quotes around the function path or pattern name, otherwise the value will be interpreted as a context variable!

verbatim

Stops the template engine from rendering the contents of this block tag.

A common use is to allow a Javascript template layer that collides with Djangos syntax. For example:

{% verbatim %}
    {{if dying}}Still alive.{{/if}}
{% endverbatim %}

You can also designate a specific closing tag, allowing the use of {% endverbatim %} as part of the unrendered contents:

{% verbatim myblock %}
    Avoid template rendering via the {% verbatim %}{% endverbatim %} block.
{% endverbatim myblock %}

widthratio

For creating bar charts and such, this tag calculates the ratio of a given value to a maximum value, and then applies that ratio to a constant.

For example:

<img src="bar.png" alt="Bar"
     height="10" width="{% widthratio this_value max_value max_width %}" />

If this_value is 175, max_value is 200, and max_width is 100, the image in the above example will be 88 pixels wide (because 175/200 = .875; .875 * 100 = 87.5 which is rounded up to 88).

In some cases you might want to capture the result of widthratio in a variable. It can be useful, for instance, in a blocktrans like this:

{% widthratio this_value max_value max_width as width %}
{% blocktrans %}The width is: {{ width }}{% endblocktrans %}

with

Caches a complex variable under a simpler name. This is useful when accessing an expensive method (e.g., one that hits the database) multiple times.

For example:

{% with total=business.employees.count %}
    {{ total }} employee{{ total|pluralize }}
{% endwith %}

The populated variable (in the example above, total) is only available between the {% with %} and {%endwith %} tags.

You can assign more than one context variable:

{% with alpha=1 beta=2 %}
    ...
{% endwith %}

Note

The previous more verbose format is still supported: {% with business.employees.count as total %}

Built-in filter reference

add

Adds the argument to the value.

For example:

{{ value|add:"2" }}

If value is 4, then the output will be 6.

This filter will first try to coerce both values to integers. If this fails, itll attempt to add the values together anyway. This will work on some data types (strings, list, etc.) and fail on others. If it fails, the result will be an empty string.

For example, if we have:

{{ first|add:second }}

and first is [1, 2, 3] and second is [4, 5, 6], then the output will be [1, 2, 3, 4, 5, 6].

Warning

Strings that can be coerced to integers will be summed, not concatenated, as in the first example above.

addslashes

Adds slashes before quotes. Useful for escaping strings in CSV, for example.

For example:

{{ value|addslashes }}

If value is "I"m using Django", the output will be "I"m using Django".

capfirst

Capitalizes the first character of the value. If the first character is not a letter, this filter has no effect.

For example:

{{ value|capfirst }}

If value is "django", the output will be "Django".

center

Centers the value in a field of a given width.

For example:

"{{ value|center:"15" }}"

If value is "Django", the output will be " Django ".

cut

Removes all values of arg from the given string.

For example:

{{ value|cut:" " }}

If value is "String with spaces", the output will be "Stringwithspaces".

date

Formats a date according to the given format.

Uses a similar format as PHPs date() function (http://php.net/date) with some differences.

Note

These format characters are not used in Django outside of templates. They were designed to be compatible with PHP to ease transitioning for designers.

Available format strings:

Format character	Description	Example output
a	"a.m." or "p.m." (Note that this is slightly different than PHPs output, because this includes periods to match Associated Press style.)	"a.m."
A	"AM" or "PM".	"AM"
b	Month, textual, 3 letters, lowercase.	"jan"
B	Not implemented.
c	ISO 8601 format. (Note: unlike others formatters, such as Z, O or r, the c formatter will not add timezone offset if value is a naive datetime (seedatetime.tzinfo).	2008-01-02T10:30:00.000123+02:00, or 2008-01-02T10:30:00.000123 if the datetime is naive
d	Day of the month, 2 digits with leading zeros.	"01" to "31"
D	Day of the week, textual, 3 letters.	"Fri"
e	Timezone name. Could be in any format, or might return an empty string, depending on the datetime.	"", "GMT", "-500", "US/Eastern", etc.
E	Month, locale specific alternative representation usually used for long date representation.	"listopada" (for Polish locale, as opposed to "Listopad")
f	Time, in 12-hour hours and minutes, with minutes left off if theyre zero. Proprietary extension.	"1", "1:30"
F	Month, textual, long.	"January"
g	Hour, 12-hour format without leading zeros.	"1" to "12"
G	Hour, 24-hour format without leading zeros.	"0" to "23"
h	Hour, 12-hour format.	"01" to "12"
H	Hour, 24-hour format.	"00" to "23"
i	Minutes.	"00" to "59"
I	Daylight Savings Time, whether its in effect or not.	"1" or "0"
j	Day of the month without leading zeros.	"1" to "31"
l	Day of the week, textual, long.	"Friday"
L	Boolean for whether its a leap year.	True or False
m	Month, 2 digits with leading zeros.	"01" to "12"
M	Month, textual, 3 letters.	"Jan"
n	Month without leading zeros.	"1" to "12"
N	Month abbreviation in Associated Press style. Proprietary extension.	"Jan.", "Feb.", "March", "May"
o	ISO-8601 week-numbering year, corresponding to the ISO-8601 week number (W)	"1999"
O	Difference to Greenwich time in hours.	"+0200"
P	Time, in 12-hour hours, minutes and a.m./p.m., with minutes left off if theyre zero and the special-case strings midnight and noon if appropriate. Proprietary extension.	"1 a.m.", "1:30 p.m.", "midnight", "noon", "12:30 p.m."
r	RFC 2822 formatted date.	"Thu, 21 Dec 2000 16:01:07 +0200"
s	Seconds, 2 digits with leading zeros.	"00" to "59"
S	English ordinal suffix for day of the month, 2 characters.	"st", "nd", "rd" or "th"
t	Number of days in the given month.	28 to 31
T	Time zone of this machine.	"EST", "MDT"
u	Microseconds.	000000 to 999999
U	Seconds since the Unix Epoch (January 1 1970 00:00:00 UTC).
w	Day of the week, digits without leading zeros.	"0" (Sunday) to "6" (Saturday)
W	ISO-8601 week number of year, with weeks starting on Monday.	1, 53
y	Year, 2 digits.	"99"
Y	Year, 4 digits.	"1999"
z	Day of the year.	0 to 365
Z	Time zone offset in seconds. The offset for timezones west of UTC is always negative, and for those east of UTC is always positive.	-43200 to 43200

For example:

{{ value|date:"D d M Y" }}

If value is a datetime object (e.g., the result of datetime.datetime.now()), the output will be the string "Wed 09Jan 2008".

The format passed can be one of the predefined ones DATE_FORMAT, DATETIME_FORMAT, SHORT_DATE_FORMAT orSHORT_DATETIME_FORMAT, or a custom format that uses the format specifiers shown in the table above. Note that predefined formats may vary depending on the current locale.

Assuming that USE_L10N is True and LANGUAGE_CODE is, for example, "es", then for:

{{ value|date:"SHORT_DATE_FORMAT" }}

the output would be the string "09/01/2008" (the "SHORT_DATE_FORMAT" format specifier for the es locale as shipped with Django is "d/m/Y").

When used without a format string:

{{ value|date }}

…the formatting string defined in the DATE_FORMAT setting will be used, without applying any localization.

You can combine date with the time filter to render a full representation of a datetime value. E.g.:

{{ value|date:"D d M Y" }} {{ value|time:"H:i" }}

default

If value evaluates to False, uses the given default. Otherwise, uses the value.

For example:

{{ value|default:"nothing" }}

If value is "" (the empty string), the output will be nothing.

default_if_none

If (and only if) value is None, uses the given default. Otherwise, uses the value.

Note that if an empty string is given, the default value will not be used. Use the default filter if you want to fallback for empty strings.

For example:

{{ value|default_if_none:"nothing" }}

If value is None, the output will be the string "nothing".

dictsort

Takes a list of dictionaries and returns that list sorted by the key given in the argument.

For example:

{{ value|dictsort:"name" }}

If value is:

[
    {"name": "zed", "age": 19},
    {"name": "amy", "age": 22},
    {"name": "joe", "age": 31},
]

then the output would be:

[
    {"name": "amy", "age": 22},
    {"name": "joe", "age": 31},
    {"name": "zed", "age": 19},
]

You can also do more complicated things like:

{% for book in books|dictsort:"author.age" %}
    * {{ book.title }} ({{ book.author.name }})
{% endfor %}

If books is:

[
    {"title": "1984", "author": {"name": "George", "age": 45}},
    {"title": "Timequake", "author": {"name": "Kurt", "age": 75}},
    {"title": "Alice", "author": {"name": "Lewis", "age": 33}},
]

then the output would be:

* Alice (Lewis)
* 1984 (George)
* Timequake (Kurt)

dictsortreversed

Takes a list of dictionaries and returns that list sorted in reverse order by the key given in the argument. This works exactly the same as the above filter, but the returned value will be in reverse order.

divisibleby

Returns True if the value is divisible by the argument.

For example:

{{ value|divisibleby:"3" }}

If value is 21, the output would be True.

escape

Escapes a strings HTML. Specifically, it makes these replacements:

• < is converted to <
• > is converted to >
• " (single quote) is converted to '
• " (double quote) is converted to "
• & is converted to &

The escaping is only applied when the string is output, so it does not matter where in a chained sequence of filters you put escape: it will always be applied as though it were the last filter. If you want escaping to be applied immediately, use the force_escape filter.

Applying escape to a variable that would normally have auto-escaping applied to the result will only result in one round of escaping being done. So it is safe to use this function even in auto-escaping environments. If you want multiple escaping passes to be applied, use the force_escape filter.

For example, you can apply escape to fields when autoescape is off:

{% autoescape off %}
    {{ title|escape }}
{% endautoescape %}

escapejs

Escapes characters for use in JavaScript strings. This does not make the string safe for use in HTML, but does protect you from syntax errors when using templates to generate JavaScript/JSON.

For example:

{{ value|escapejs }}

If value is "testing javascript "string" <b>escaping</b>", the output will be"testingu000Du000Ajavascript u0027stringu0022 u003Cbu003Eescapingu003C/bu003E".

filesizeformat

Formats the value like a human-readable file size (i.e. "13 KB", "4.1 MB", "102 bytes", etc).

For example:

{{ value|filesizeformat }}

If value is 123456789, the output would be 117.7 MB.

File sizes and SI units

Strictly speaking, filesizeformat does not conform to the International System of Units which recommends using KiB, MiB, GiB, etc. when byte sizes are calculated in powers of 1024 (which is the case here). Instead, Django uses traditional unit names (KB, MB, GB, etc.) corresponding to names that are more commonly used.

first

Returns the first item in a list.

For example:

{{ value|first }}

If value is the list ["a", "b", "c"], the output will be "a".

floatformat

When used without an argument, rounds a floating-point number to one decimal place but only if theres a decimal part to be displayed. For example:

value	Template	Output
34.23234	{{ value|floatformat }}	34.2
34.00000	{{ value|floatformat }}	34
34.26000	{{ value|floatformat }}	34.3

If used with a numeric integer argument, floatformat rounds a number to that many decimal places. For example:

value	Template	Output
34.23234	{{ value|floatformat:3 }}	34.232
34.00000	{{ value|floatformat:3 }}	34.000
34.26000	{{ value|floatformat:3 }}	34.260

Particularly useful is passing 0 (zero) as the argument which will round the float to the nearest integer.

value	Template	Output
34.23234	{{ value|floatformat:"0" }}	34
34.00000	{{ value|floatformat:"0" }}	34
39.56000	{{ value|floatformat:"0" }}	40

If the argument passed to floatformat is negative, it will round a number to that many decimal places but only if theres a decimal part to be displayed. For example:

value	Template	Output
34.23234	{{ value|floatformat:"-3" }}	34.232
34.00000	{{ value|floatformat:"-3" }}	34
34.26000	{{ value|floatformat:"-3" }}	34.260

Using floatformat with no argument is equivalent to using floatformat with an argument of -1.

force_escape

Applies HTML escaping to a string (see the escape filter for details). This filter is applied immediately and returns a new, escaped string. This is useful in the rare cases where you need multiple escaping or want to apply other filters to the escaped results. Normally, you want to use the escape filter.

For example, if you want to catch the <p> HTML elements created by the linebreaks filter:

{% autoescape off %}
    {{ body|linebreaks|force_escape }}
{% endautoescape %}

get_digit

Given a whole number, returns the requested digit, where 1 is the right-most digit, 2 is the second-right-most digit, etc. Returns the original value for invalid input (if input or argument is not an integer, or if argument is less than 1). Otherwise, output is always an integer.

For example:

{{ value|get_digit:"2" }}

If value is 123456789, the output will be 8.

iriencode

Converts an IRI (Internationalized Resource Identifier) to a string that is suitable for including in a URL. This is necessary if youre trying to use strings containing non-ASCII characters in a URL.

Its safe to use this filter on a string that has already gone through the urlencode filter.

For example:

{{ value|iriencode }}

If value is "?test=1&me=2", the output will be "?test=1&me=2".

join

Joins a list with a string, like Pythons str.join(list)

For example:

{{ value|join:" // " }}

If value is the list ["a", "b", "c"], the output will be the string "a // b // c".

last

Returns the last item in a list.

For example:

{{ value|last }}

If value is the list ["a", "b", "c", "d"], the output will be the string "d".

length

Returns the length of the value. This works for both strings and lists.

For example:

{{ value|length }}

If value is ["a", "b", "c", "d"] or "abcd", the output will be 4.

Changed in version 1.8: The filter returns 0 for an undefined variable. Previously, it returned an empty string.

length_is

Returns True if the values length is the argument, or False otherwise.

For example:

{{ value|length_is:"4" }}

If value is ["a", "b", "c", "d"] or "abcd", the output will be True.

linebreaks

Replaces line breaks in plain text with appropriate HTML; a single newline becomes an HTML line break (<br />) and a new line followed by a blank line becomes a paragraph break (</p>).

For example:

{{ value|linebreaks }}

If value is Joel is a slug, the output will be <p>Joel<br />is a slug</p>.

linebreaksbr

Converts all newlines in a piece of plain text to HTML line breaks (<br />).

For example:

{{ value|linebreaksbr }}

If value is Joel is a slug, the output will be Joel<br />is a slug.

linenumbers

Displays text with line numbers.

For example:

{{ value|linenumbers }}

If value is:

one
two
three

the output will be:

1. one
2. two
3. three

ljust

Left-aligns the value in a field of a given width.

Argument: field size

For example:

"{{ value|ljust:"10" }}"

If value is Django, the output will be "Django ".

lower

Converts a string into all lowercase.

For example:

{{ value|lower }}

If value is Still MAD At Yoko, the output will be still mad at yoko.

make_list

Returns the value turned into a list. For a string, its a list of characters. For an integer, the argument is cast into an unicode string before creating a list.

For example:

{{ value|make_list }}

If value is the string "Joel", the output would be the list ["J", "o", "e", "l"]. If value is 123, the output will be the list ["1", "2", "3"].

phone2numeric

Converts a phone number (possibly containing letters) to its numerical equivalent.

The input doesnt have to be a valid phone number. This will happily convert any string.

For example:

{{ value|phone2numeric }}

If value is 800-COLLECT, the output will be 800-2655328.

pluralize

Returns a plural suffix if the value is not 1. By default, this suffix is "s".

Example:

You have {{ num_messages }} message{{ num_messages|pluralize }}.

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