Filters.md

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web-clipper/filters

Filters allow you to modify [[variables]] in [[Obsidian Web Clipper/Templates|Web Clipper templates]]. Filters are applied to variables using the syntax {{variable|filter}}.

• Filters work for any kind of [[Variables|variable]] including prompt, meta, selector, and schema variables.
• Filters can be chained, e.g. {{variable|filter1|filter2}}, and are applied in the order they are added.

Dates

Convert and modify dates.

date

Converts a date to the specified format, see reference.

• {{date|date:"YYYY-MM-DD"}} converts the current date to "YYYY-MM-DD".
• Use date:("outputFormat", "inputFormat") to specify the input format, e.g. "12/01/2024"|date:("YYYY-MM-DD", "MM/DD/YYYY") parses "12/01/2024" and returns "2024-12-01".

date_modify

Modifies a date by adding or subtracting a specified amount of time, see reference.

• "2024-12-01"|date_modify:"+1 year" returns "2025-12-01"
• "2024-12-01"|date_modify:"- 2 months" returns "2024-10-01"

Text conversion and capitalization

Convert text strings from one format to another.

camel

Converts text to camelCase.

capitalize

Capitalizes the first character of the value and converts the rest to lowercase, e.g. "hELLO wORLD"|capitalize returns "Hello world".

kebab

Converts text to kebab-case.

lower

Converts text to lowercase.

pascal

Converts text to PascalCase.

replace

Replaces occurrences of specified text:

• Simple replacement: "hello!"|replace:",":"" removes all commas.
• Multiple replacements: "hello world"|replace:("e":"a","o":"0") returns "hall0 w0rld".
• Replacements are applied in the order they are specified.
• To remove specified text, use "" as the replacement value.
• Special characters including : | { } ( ) ' " should be escaped with a backslash when used in the search term, e.g. \: to search for a literal colon.

Regex is supported using JavaScript regex syntax:

• Replace all vowels: "hello world"|replace:"/[aeiou]/g":"*" → "h*ll* w*rld".
• Case-insensitive: "HELLO world"|replace:"/hello/i":"hi" → "hi world".
• Multiple regex: "hello world"|replace:("/[aeiou]/g":"*","/\s+/":"-") → "h*ll*-w*rld".
• Available flags: g (global), i (case-insensitive), m (multiline), s (dotAll), u (unicode), y (sticky).

safe_name

Converts text to a safe file name.

• By default, safe_name applies the most conservative sanitization rules.
• OS-specific rules can be applied with safe_name:os where os can be windows, mac, or linux to only apply the rules for that operating system.

snake

Converts text to snake_case.

title

Converts text to Title Case, e.g. "hello world"|title returns "Hello World".

trim

Removes white space from both ends of a string.

• " hello world "|trim returns "hello world".

uncamel

Converts camelCase or PascalCase to space-separated words, which you can further format with other filters like title or capitalize.

• "camelCase"|uncamel returns "camel case".
• "PascalCase"|uncamel returns "pascal case".

upper

Converts a value to uppercase, e.g. "hello world"|upper returns "HELLO WORLD".

Text formatting

Apply [[Basic formatting syntax]] and [[Advanced formatting syntax]] to text.

blockquote

Adds a Markdown quote prefix (> ) to each line of the input.

callout

Creates a [[Callouts|callout]] with optional parameters: {{variable|callout:("type", "title", foldState)}}

• type is the callout type, and defaults to "info"
• title is the callout title, and defaults to empty
• foldState is a boolean to set the fold state (true for folded, false for unfolded, null for not foldable)
• footnote converts an array or object into a list of Markdown footnotes.
• For arrays: ["first item","second item"]|footnote returns: [^1]: first item etc.
• For objects: {"First Note": "Content 1", "Second Note": "Content 2"}|footnote returns: [^first-note]: Content 1 etc.

fragment_link

Converts strings and arrays into text fragment links. Defaults to "link" for the link text.

• highlights|fragment returns Highlight content [link](text-fragment-url)
• highlights|fragment:"custom title" returns Highlight content [custom title](text-fragment-url)
• image converts strings, arrays, or objects into Markdown image syntax.
• For strings: "image.jpg"|image:"alt text" returns ![alt text](image.jpg).
• For arrays: ["image1.jpg","image2.jpg"]|image:"alt text" returns an array of Markdown image strings with the same alt text for all images.
• For objects: {"image1.jpg": "Alt 1", "image2.jpg": "Alt 2"}|image returns Markdown image strings with alt text from the object keys.

link

Converts strings, arrays, or objects into Markdown link syntax (not to be confused with [[Filters#wikilink|wikilink]]).

• For strings: "url"|link:"author" returns [author](url).
• For arrays: ["url1","url2"]|link:"author" returns an array of Markdown links with the same text for all links.
• For objects: {"url1": "Author 1", "url2": "Author 2"}|link returns Markdown links with the text that matches the object keys.

list

Converts an array to a Markdown list.

• Use list to convert to a bullet list.
• Use list:task to convert to a task list.
• Use list:numbered to convert to a numbered list.
• Use list:numbered-task to convert to a task list with numbers.

table

Converts an array or array of objects into a [[Advanced formatting syntax#Tables|Markdown table]]:

• For an array of objects, it uses the object keys as headers.
• For an array of arrays, it creates a table with each nested array as a row.
• For a simple array, it creates a single-column table with "Value" as the header.

wikilink

Converts strings, arrays, or objects into Obsidian [[Link notes|wikilink]] syntax.

• For strings: "page"|wikilink returns [[page]].
• For strings with alias: "page"|wikilink:"alias" returns [[page|alias]].
• For arrays: ["page1","page2"]|wikilink returns an array of wikilinks without aliases.
• For arrays with alias: ["page1","page2"]|wikilink:"alias" returns an array of wikilinks with the same alias for all links.
• For objects: {"page1": "alias1", "page2": "alias2"}|wikilink returns wikilinks with the keys as page names and values as aliases.

Numbers

calc

Performs basic arithmetic operations on numbers.

• Supports operators: +, -, *, /, ** (or ^) for exponentiation.
• Example: "5"|calc:"+10" returns "15".
• Example: "2"|calc:"**3" returns "8" (2 cubed).
• Returns the original string if the input is not a number.

length

Returns the length of strings, arrays, or number of keys in objects.

• For strings: "hello"|length returns "5".
• For arrays: ["a","b","c"]|length returns "3".
• For objects: {"a":1,"b":2}|length returns "2".

round

Rounds a number to the nearest integer or to a specified number of decimal places.

• Without parameters: 3.7|round returns 4.
• With decimal places specified: 3.14159|round:2 returns 3.14.

HTML processing

Process HTML content and convert HTML to Markdown. Note that your input [[Variables|variable]] must contain HTML content, e.g. using {{fullHtml}}, {{contentHtml}} or a {{selectorHtml:}} variable.

markdown

Converts a string to an [[Obsidian Flavored Markdown]] formatted string.

• Useful when combined with variables that return HTML such as {{contentHtml}}, {{fullHtml}}, and selector variables like {{selectorHtml:cssSelector}}.

remove_attr

Removes only the specified HTML attributes from tags.

• Example: "<div class="test" id="example">Content</div>"|remove_attr:"class" returns <div id="example">Content</div>.
• Multiple attributes: {{contentHtml|remove_attr:("class,style,id")}}

remove_html

Removes the specified HTML elements and their content from a string.

• Supports tag name, class, or id, e.g. {{contentHtml|remove_html:("img,.class-name,#element-id")}}
• To remove only HTML tags or attributes without removing the content use the strip_tags or strip_attr filters.

remove_tags

Removes only the specified HTML tags. Keeps the content of the tags.

• Example: "<p>Hello <b>world</b>!</p>"|remove_tags:"b" returns "<p>Hello world!</p>".
• Multiple tags: {{contentHtml|remove_tags:("a,em,strong")}}

replace_tags

Replaces HTML tags, maintaining the content and attributes of the tag.

• {{contentHtml|replace_tags:"strong":"h2"}} replaces all <strong> tags with <h2>.

strip_attr

Removes all HTML attributes from a string.

• Use strip_attr:("class, id") to keep specific attributes.
• Example: "<div class="test" id="example">Content</div>"|strip_attr:("class") returns <div id="example">Content</div>.

strip_md

Removes all Markdown formatting and returns a plain text string, e.g. turning **text** into text.

• Turns formatted text into unformatted plain text, including bold, italic, highlights, headers, code, blockquotes, tables, task lists, and wikilinks.
• Entirely removes tables, footnotes, images, and HTML elements.

strip_tags

Removes all HTML tags from a string. Unlike remove_html this doesn't remove the content within the tags.

• Use strip_tags:("p,strong,em") to keep specific tags.
• Example: "<p>Hello <b>world</b>!</p>"|strip_tags:("b") returns Hello <b>world</b>!.

Arrays and objects

Process arrays and objects.

first

Returns the first element of an array as a string.

• ["a","b","c"]|first returns "a".
• If the input is not an array, it returns the input unchanged.

join

Combines elements of an array into a string.

• ["a","b","c"]|join returns "a,b,c".
• A custom separator can be specified: ["a","b","c"]|join:" " returns "a b c". Use join:"\n" to separate elements with a line break.
• It can be useful after split or slice: "a,b,c,d"|split:","|slice:1,3|join:" " returns "b c".

last

Returns the last element of an array as a string.

• ["a","b","c"]|last returns "c".
• If the input is not an array, it returns the input unchanged.

map

Applies a transformation to each element of an array using the syntax map:item => item.property or map:item => item.nested.property for nested properties.

• [{gem: "obsidian", color: "black"}, {gem: "amethyst", color: "purple"}]|map:item => item.gem returns ["obsidian", "amethyst"].
• Use parentheses for object literals and complex expressions: map:item => ({key: value}), e.g.: [{gem: "obsidian", color: "black"}, {gem: "amethyst", color: "purple"}]|map:item => ({name: item.gem, color: item.color}) returns [{name: "obsidian", color: "black"}, {name: "amethyst", color: "purple"}].

String literals are supported and automatically wrapped in an object with a str property. The str property is used to store the result of string literal transformations, e.g. ["rock", "pop"]|map:item => "genres/${item}" returns [{str: "genres/rock"}, {str: "genres/pop"}].

Combine map with the template filter, e.g. map:item => ({name: ${item.gem}, color: item.color})|template:"- ${name} is ${color}\n".

object

Manipulates object data:

• object:array converts an object to an array of key-value pairs.
• object:keys returns an array of the object's keys.
• object:values returns an array of the object's values.
• Example: {"a":1,"b":2}|object:array returns [["a",1],["b",2]].

slice

Extracts a portion of a string or array.

• For strings: "hello"|slice:1,4 returns "ell".
• For arrays: ["a","b","c","d"]|slice:1,3 returns ["b","c"].
• If only one parameter is provided, it slices from that index to the end: "hello"|slice:2 returns "llo".
• Negative indices count from the end: "hello"|slice:-3 returns "llo".
• The second parameter is exclusive: "hello"|slice:1,4 includes characters at indices 1, 2, and 3.
• Using a negative second parameter excludes elements from the end: "hello"|slice:0,-2 returns "hel".

split

Divides a string into an array of substrings.

• "a,b,c"|split:"," returns ["a","b","c"].
• "hello world"|split:" " returns ["hello","world"].
• If no separator is provided, it splits on every character: "hello"|split returns ["h","e","l","l","o"].
• Regular expressions can be used as separators: "a1b2c3"|split:[0-9] returns ["a","b","c"].

template

Applies a template string to an object or array of objects, using the syntax object|template:"Template with ${variable}".

• Access nested properties: {"gem":{"name":"Obsidian"}}|template:"${gem.name}" returns "Obsidian".
• For objects: {"gem":"obsidian","hardness":5}|template:"${gem} has a hardness of ${hardness}" returns "obsidian has a hardness of 5".
• For arrays: [{"gem":"obsidian","hardness":5},{"gem":"amethyst","hardness":7}]|template:"- ${gem} has a hardness of ${hardness}\n" returns a formatted list.

Works with string literals from map by accessing the str property:

• Example: ["rock", "pop"]|map:item => "genres/${item}"|template:"${str}" returns "genres/rock\ngenres/pop".
• The str property is automatically used when applying template to objects created by map with string literals.

unique

Removes duplicate values from arrays and objects.

• For arrays of primitives: [1,2,2,3,3]|unique returns [1,2,3].
• For arrays of objects: [{"a":1},{"b":2},{"a":1}]|unique returns [{"a":1},{"b":2}].
• For objects it removes properties with duplicate values, keeping the last occurrence's key.
• For strings it returns the input unchanged.