Django template filters are powerful tools for modifying data before rendering it in templates. Filters can transform variables, format data, and apply logic. This reference guide by The Coding College provides a comprehensive list of Django’s built-in filters, along with examples to help you use them effectively.
1. String Filters
capfirst
Capitalizes the first letter of the string.
Example:
{{ "hello world" | capfirst }}
<!-- Output: Hello world -->center
Centers the string within a specified width, padding with spaces.
Example:
{{ "Django" | center:10 }}
<!-- Output: " Django " -->cut
Removes all instances of a specified substring.
Example:
{{ "hello world" | cut:"o" }}
<!-- Output: hell wrld -->title
Converts the string to title case (capitalizing each word).
Example:
{{ "django tutorial" | title }}
<!-- Output: Django Tutorial -->truncatechars
Truncates a string after a specified number of characters, appending ....
Example:
{{ "This is a long string" | truncatechars:10 }}
<!-- Output: This is a... -->truncatewords
Truncates a string after a specified number of words.
Example:
{{ "This is a long string" | truncatewords:3 }}
<!-- Output: This is a... -->2. Date and Time Filters
date
Formats a date according to the given format string.
Example:
{{ my_date | date:"F j, Y" }}
<!-- Output: December 21, 2024 -->time
Formats a time according to the given format string.
Example:
{{ my_time | time:"H:i" }}
<!-- Output: 14:35 -->timesince
Returns the time elapsed since a date.
Example:
{{ my_date | timesince }}
<!-- Output: 3 days ago -->timeuntil
Returns the time remaining until a date.
Example:
{{ my_date | timeuntil }}
<!-- Output: 2 days, 4 hours -->3. Numeric Filters
add
Adds a value to the variable.
Example:
{{ 10 | add:5 }}
<!-- Output: 15 -->divisibleby
Checks if the variable is divisible by a given value. Returns True or False.
Example:
{{ 10 | divisibleby:2 }}
<!-- Output: True -->length
Returns the length of a string, list, or queryset.
Example:
{{ "Django" | length }}
<!-- Output: 6 -->slice
Slices a list or string.
Example:
{{ "Django" | slice:":3" }}
<!-- Output: Dja -->4. Boolean Filters
yesno
Converts True, False, or None to a custom output.
Example:
{{ my_var | yesno:"Yes,No,Maybe" }}
<!-- Output: Yes (if True), No (if False), Maybe (if None) -->5. List and Dict Filters
dictsort
Sorts a list of dictionaries by a specified key.
Example:
{{ my_list | dictsort:"name" }}dictsortreversed
Sorts a list of dictionaries by a specified key in reverse order.
Example:
{{ my_list | dictsortreversed:"name" }}first
Returns the first item in a list.
Example:
{{ my_list | first }}join
Joins a list into a single string with a specified delimiter.
Example:
{{ my_list | join:", " }}
<!-- Output: item1, item2, item3 -->last
Returns the last item in a list.
Example:
{{ my_list | last }}6. Conditional Filters
default
Returns a default value if the variable is empty or undefined.
Example:
{{ my_var | default:"Default Value" }}default_if_none
Returns a default value if the variable is None.
Example:
{{ my_var | default_if_none:"Default Value" }}7. Escaping and Formatting Filters
escape
Escapes HTML characters to prevent XSS attacks.
Example:
{{ "<b>bold</b>" | escape }}
<!-- Output: <b>bold</b> -->safe
Marks a string as safe, allowing it to render as raw HTML.
Example:
{{ "<b>bold</b>" | safe }}
<!-- Output: <b>bold</b> -->floatformat
Formats a number to a fixed number of decimal places.
Example:
{{ 123.456 | floatformat:2 }}
<!-- Output: 123.46 -->Final Thoughts
Django filters are essential for creating dynamic, flexible templates. By mastering these filters, you can effectively manage data presentation and simplify template logic.
For more tutorials and resources, visit The Coding College!