String Filters

Filters for transforming and manipulating text strings.

Case Transformation

Filter	Description
upper	Convert to uppercase
lower	Convert to lowercase
title	Convert to title case
capitalize	Capitalize first letter, lowercase rest

{{ post.title|upper }}          <!-- HELLO WORLD -->
{{ post.title|lower }}          <!-- hello world -->
{{ post.title|title }}          <!-- Hello World -->
{{ post.title|capitalize }}     <!-- Hello world -->

Trimming

Filter	Arguments	Description
trim	character_mask, side	Remove characters from string

Arguments:

• character_mask — Characters to trim (default: whitespace)
• side — 'both' (default), 'left', or 'right'

{{ post.title|trim }}                  <!-- Remove whitespace -->
{{ post.title|trim('/') }}             <!-- Remove slashes -->
{{ post.title|trim(' ', 'left') }}     <!-- Trim left only -->
{{ post.title|trim(' ', 'right') }}    <!-- Trim right only -->

Truncation

Filter	Arguments	Description
truncate	len, more	Trim to word count, keeping some tags

Arguments:

• len — Number of words (default: 55)
• more — Appended when the text is cut (default: '…')

{{ post.excerpt|truncate(20) }}                <!-- First 20 words… -->
{{ post.content|truncate(30) }}                <!-- Keeps paragraphs and links -->
{{ post.title|truncate(5, '...') }}

truncate counts words, as in Timber. It keeps the p, a, span, b, i, br and blockquote tags, removes the others and closes the ones a cut leaves open, without ever cutting inside a tag. To count characters, use excerpt_chars; to remove every tag, excerpt.

Excerpt

Filter	Arguments	Description
excerpt	num_words, more	Trim to word count
excerpt_chars	num_chars, more	Trim to character count

excerpt Arguments:

• num_words — Number of words (default: 55, as in WordPress)
• more — Suffix text (default: '…')

excerpt_chars Arguments:

• num_chars — Number of characters (default: 60)
• more — Suffix text (default: '…')

{{ post.content|excerpt }}             <!-- 55 words -->
{{ post.content|excerpt(25) }}         <!-- 25 words -->
{{ post.content|excerpt(25, '...') }}

{{ post.content|excerpt_chars(200) }}
{{ post.content|excerpt_chars(200, '...') }}

HTML Processing

Filter	Arguments	Description
striptags	allowable_tags	Remove HTML tags
nl2br	—	Convert newlines to <br> tags
spaceless	—	Remove whitespace between HTML tags
pretags	—	Escape HTML inside <pre> tags

{{ post.content|striptags }}                      <!-- Remove all tags -->
{{ post.content|striptags('<p><a>')|kses_post }}  <!-- Keep p and a tags -->
{{ text|nl2br }}                                  <!-- Newlines to <br> -->
{{ post.content|spaceless }}                      <!-- Remove tag whitespace -->

striptags returns text, escaped like any value, as in Twig: the tags you keep print as text unless you end with |kses_post.

nl2br, spaceless and pretags output HTML. A text value is escaped before them, so its own tags stay text: {{ post.meta('bio')|nl2br }} adds <br> without letting HTML from the field through. spaceless and pretags therefore only have tags to work on in a field that outputs HTML, such as post.content.

Text Manipulation

Filter	Arguments	Description
replace	from, to or {map}	Replace text
split	delimiter, limit	Split into array
slug	separator	Create URL-friendly slug
sanitize	separator	Alias for slug

replace formats:

• Simple: replace('old', 'new')
• Map: replace({'%name%': 'World', '%age%': '30'})

{{ post.title|replace('old', 'new') }}
{{ post.title|replace({'%name%': user.name}) }}
{{ 'red,green,blue'|split(',')|join(' / ') }}        <!-- red / green / blue -->
{{ 'one,two,three,four'|split(',', 3)|last }}      <!-- three,four -->
{{ 'abc'|split('')|join(' ') }}                    <!-- a b c: one item per character -->
{{ post.title|slug }}                  <!-- hello-world -->
{{ post.title|slug('_') }}             <!-- hello_world -->

Formatting

Filter	Arguments	Description
format	...values	sprintf-style formatting
url_encode	—	URL encode string
relative	—	Convert absolute URL to relative

{{ '%s has %d posts'|format(user.name, count) }}
{{ search_query|url_encode }}
{{ post.link|relative }}               <!-- /2024/01/post-slug/ -->