All filters

Grouped by functionality.

This is a based info on the CloudCannon Jekyll cheatsheet. See also Liquid filters on Jekyll docs.

The items here are grouped and ordered by use, rather than alpabetically.

For escaping a URI:

• url_escape
• cgi_escape

For escaping HTML tags:

• xml_escape
• escape
• escape_once

See also the Arrays cheatsheet.

String filters

• append

  {{ 'jekyll' | append: '.jpg' }}

• prepend

  {{ 'Jekyll' | prepend: 'I love ' }}

• slice

  Get items in an iterable from start index (inclusive) for a limit of items. See also slice in Array section and below offset and limit in the For loops page.

  {{ "hello" | slice: 0 }} <!-- h -->
  {{ "hello" | slice: 1 }} <!-- e -->
  {{ "hello" | slice: 2, 3 }} <!-- ell -->

• markdownify
• jsonify

  {{ my_var | jsonify }}
  {{ site.data.my_data | jsonify }}

• inspect

  Show a value as a Ruby object. Useful for debugging. Especially useful if a value is possibly null and therefore invisible or if you have a data structure to understand.

  {{ my_var | inspect }}
  {{ site.page | inspect }}

• date
• default

  {% assign new_var = foo | default: 'fallback' %}
  {% assign new_var = bar.buzz | default: 'fallback' %}

• replace

  Warning - if you do replace on an array, it converts it to a string.

• replace_first
• strip
• lstrip
• rstrip
• capitalize
• downcase
• upcase
• split

  {{ my_str | split: ',' }}

• truncate

  Truncate a string down to x characters

• truncatewords

  Truncate a string down to x words

• strip_html
• strip_newlines

  Remove \n characters

• newline_to_br

  Convert \n to two br tags

• escape

  Escape HTML so that tags appear as ampersand charactes that aren’t evaluated

  {{ "<p>Jekyll</p>" | escape }}
  
  Result:
  
  &amp;lt;p&amp;gt;Jekyll&amp;lt;/p&amp;gt;

• uri_escape

  Escape a URI with percent coding

  {{ "foo, bar \baz?" | uri_escape }}
  
  Result:
  
  foo,%20bar%20%5Cbaz?

• url_decode
• url_encode
• slugify

  {{ "The _config.yml file" | slugify }} <!-- the-config-yml-file -->

Array filters

• join

  {{ my_array | join: ', ' }}

• first

  {{ my_array | first }}

• last

  {{ my_array | last }}

• concat

  Combine to arrays - parameter must be of type array to avoid error

  ---
  foo:
    - abc
    - def
  bar:
    - 123
  ---
  {{ page.foo | concat: page.bar | inspect }}

• slice

  Get an item by index. Or with two values as a range, set a start index and a count of elements. See also offset and limit on the For loops page.

  ---
  foo: ['abc', 'def', 'ghi', 'jkl', 'mno' ]
  ---
  {{ page.foo | slice: 0 }} <!-- 1st element -->
  {{ page.foo | slice: 3 }} <!-- 4th element -->
  {{ page.foo | slice: 0, 3 }} <!-- First three elements -->
  {{ page.foo | slice: 1, 3 }} <!-- First 3 elements starting at 2nd element -->

• map

  {{ my_array | map: "some_attribute" }}

• where

  A simple filter where an attribute value matches a given value.

  {{ site.posts | where: "category", "foo" }}
  {{ page.people | where: "school", "Stanford" }}

• where_exp

  A filter where a given expression is true.

  {{ page.people | where_exp: "item", "item.name contains 'Jo'" }}
  {{ page.people | where_exp: "item", "item.year >= 2016" }}
  {{ page.people | where_exp: "item", "item.school != "Stanford" }}

• group_by

  Group an array’s items by a given property. You’ll get a hash where that attribute is used as the key and the value is all the match items (the attribute is not removed).

  {{ page.people | group_by: country }}
  <!--
    Source:
        [ [name: 'Joe', country: 'England'], [name: 'Sally', country: 'England']
    Result:
        { England: [ [name: 'Joe', country: 'England'], [name: 'Sally', country: 'England'] ] }
  -->

• group_by_exp

  {{ page.people | group_by_exp: "item", "item.name | size" }}
  {{ page.people | group_by_exp: "item", "item.year | modulo: 2" }}
  {{ page.people | group_by_exp: "item", "item.country | replace: 'rd', 'ry' " }}

• size

  {{ my_array | size }}

• reverse

  {{ my_array | reverse }}

• sort

  {{ my_array | sort }}
  {{ page.posts | sort: 'author' }}

• sort_natural

  Sorts items in an array in case-insensitive order

  {% assign my_array = "zebra, octopus, giraffe, Sally Snake" | split: ", " %}
  {{ my_array | sort_natural | join: ", " }}

• uniq

  You don’t have to sort, but if you do then your results will read better.

  {{ my_array | uniq }}
  {{ my_array | sort | uniq }}

• push

  Insert at the end of the array

  {% assign my_array = my_array | push: 'my value ' %}

• pop

  Remove an item from the end of an array. Accepts optional param num which defaults to 1

  {% assign value = my_array | pop %}
  {% assign value = my_array | pop: 1 %}

• unshift

  Insert at the start of the array

  {% assign my_array = my_array | unshift: 'my value ' %}

• shift

  Remove an item from the start of an array. Accepts optional param num which defaults to 1

  {% assign value = my_array | shift %}
  {% assign value = my_array | shift: 1 %}

• compact

  Removes any nil values from an array.

  {% assign site_categories = site.pages | map: "category" | compact %}

Maths

• plus

  {{ 4 | plus: 2 }}

• minus
• times
• divided_by
• modulo
• floor
• ceil
• round
• abs
• at_least

  Limits a number to a minimum value. Same as min(a, b) in other languages.

  {{ 4 | at_least: 3 }} <!-- 3 -- >

• at_most

  Limits a number to a maximum value. Same as max(a, b) in other languages.