hugo/content/en/content-management/front-matter.md
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---
title: Front Matter
linktitle:
description: Hugo allows you to add front matter in yaml, toml, or json to your content files.
date: 2017-01-09
publishdate: 2017-01-09
lastmod: 2017-02-24
categories: [content management]
keywords: ["front matter", "yaml", "toml", "json", "metadata", "archetypes"]
menu:
docs:
parent: "content-management"
weight: 30
weight: 30 #rem
draft: false
aliases: [/content/front-matter/]
toc: true
---
**Front matter** allows you to keep metadata attached to an instance of a [content type][]---i.e., embedded inside a content file---and is one of the many features that gives Hugo its strength.
{{< youtube Yh2xKRJGff4 >}}
## Front Matter Formats
Hugo supports four formats for front matter, each with their own identifying tokens.
TOML
: identified by opening and closing `+++`.
YAML
: identified by opening and closing `---`.
JSON
: a single JSON object surrounded by '`{`' and '`}`', followed by a new line.
ORG
: a group of Org mode keywords in the format '`#+KEY: VALUE`'. Any line that does not start with `#+` ends the front matter section.
Keyword values can be either strings (`#+KEY: VALUE`) or a whitespace separated list of strings (`#+KEY[]: VALUE_1 VALUE_2`).
### Example
{{< code-toggle >}}
title = "spf13-vim 3.0 release and new website"
description = "spf13-vim is a cross platform distribution of vim plugins and resources for Vim."
tags = [ ".vimrc", "plugins", "spf13-vim", "vim" ]
date = "2012-04-06"
categories = [
"Development",
"VIM"
]
slug = "spf13-vim-3-0-release-and-new-website"
{{< /code-toggle >}}
## Front Matter Variables
### Predefined
There are a few predefined variables that Hugo is aware of. See [Page Variables][pagevars] for how to call many of these predefined variables in your templates.
aliases
: an array of one or more aliases (e.g., old published paths of renamed content) that will be created in the output directory structure . See [Aliases][aliases] for details.
audio
: an array of paths to audio files related to the page; used by the `opengraph` [internal template](/templates/internal) to populate `og:audio`.
cascade
: a map of Front Matter keys whose values are passed down to the page's descendents unless overwritten by self or a closer ancestor's cascade. See [Front Matter Cascade](#front-matter-cascade) for details.
date
: the datetime assigned to this page. This is usually fetched from the `date` field in front matter, but this behaviour is configurable.
description
: the description for the content.
draft
: if `true`, the content will not be rendered unless the `--buildDrafts` flag is passed to the `hugo` command.
expiryDate
: the datetime at which the content should no longer be published by Hugo; expired content will not be rendered unless the `--buildExpired` flag is passed to the `hugo` command.
headless
: if `true`, sets a leaf bundle to be [headless][headless-bundle].
images
: an array of paths to images related to the page; used by [internal templates](/templates/internal) such as `_internal/twitter_cards.html`.
isCJKLanguage
: if `true`, Hugo will explicitly treat the content as a CJK language; both `.Summary` and `.WordCount` work properly in CJK languages.
keywords
: the meta keywords for the content.
layout
: the layout Hugo should select from the [lookup order][lookup] when rendering the content. If a `type` is not specified in the front matter, Hugo will look for the layout of the same name in the layout directory that corresponds with a content's section. See ["Defining a Content Type"][definetype]
lastmod
: the datetime at which the content was last modified.
linkTitle
: used for creating links to content; if set, Hugo defaults to using the `linktitle` before the `title`. Hugo can also [order lists of content by `linktitle`][bylinktitle].
markup
: **experimental**; specify `"rst"` for reStructuredText (requires`rst2html`) or `"md"` (default) for Markdown.
outputs
: allows you to specify output formats specific to the content. See [output formats][outputs].
publishDate
: if in the future, content will not be rendered unless the `--buildFuture` flag is passed to `hugo`.
resources
: used for configuring page bundle resources. See [Page Resources][page-resources].
series
: an array of series this page belongs to, as a subset of the `series` [taxonomy](/content-management/taxonomies/); used by the `opengraph` [internal template](/templates/internal) to populate `og:see_also`.
slug
: appears as the tail of the output URL. A value specified in front matter will override the segment of the URL based on the filename.
summary
: text used when providing a summary of the article in the `.Summary` page variable; details available in the [content-summaries](/content-management/summaries/) section.
title
: the title for the content.
type
: the type of the content; this value will be automatically derived from the directory (i.e., the [section][]) if not specified in front matter.
url
: the full path to the content from the web root. It makes no assumptions about the path of the content file. It also ignores any language prefixes of
the multilingual feature.
videos
: an array of paths to videos related to the page; used by the `opengraph` [internal template](/templates/internal) to populate `og:video`.
weight
: used for [ordering your content in lists][ordering]. Lower weight gets higher precedence. So content with lower weight will come first. If set, weights should be non-zero, as 0 is interpreted as an *unset* weight.
\<taxonomies\>
: field name of the *plural* form of the index. See `tags` and `categories` in the above front matter examples. _Note that the plural form of user-defined taxonomies cannot be the same as any of the predefined front matter variables._
{{% note "Hugo's Default URL Destinations" %}}
If neither `slug` nor `url` is present and [permalinks are not configured otherwise in your site `config` file](/content-management/urls/#permalinks), Hugo will use the filename of your content to create the output URL. See [Content Organization](/content-management/organization) for an explanation of paths in Hugo and [URL Management](/content-management/urls/) for ways to customize Hugo's default behaviors.
{{% /note %}}
### User-Defined
You can add fields to your front matter arbitrarily to meet your needs. These user-defined key-values are placed into a single `.Params` variable for use in your templates.
The following fields can be accessed via `.Params.include_toc` and `.Params.show_comments`, respectively. The [Variables][] section provides more information on using Hugo's page- and site-level variables in your templates.
{{< code-toggle copy="false" >}}
include_toc: true
show_comments: false
{{</ code-toggle >}}
## Front Matter Cascade
Any node or section can pass down to descendents a set of Front Matter values as long as defined underneath the reserved `cascade` Front Matter key.
### Example
In `content/blog/_index.md`
{{< code-toggle copy="false" >}}
title: Blog
cascade:
banner: images/typewriter.jpg
{{</ code-toggle >}}
With the above example the Blog section page and its descendents will return `images/typewriter.jpg` when `.Params.banner` is invoked unless:
- Said descendent has its own `banner` value set
- Or a closer ancestor node has its own `cascade.banner` value set.
## Order Content Through Front Matter
You can assign content-specific `weight` in the front matter of your content. These values are especially useful for [ordering][ordering] in list views. You can use `weight` for ordering of content and the convention of [`<TAXONOMY>_weight`][taxweight] for ordering content within a taxonomy. See [Ordering and Grouping Hugo Lists][lists] to see how `weight` can be used to organize your content in list views.
## Override Global Markdown Configuration
It's possible to set some options for Markdown rendering in a content's front matter as an override to the [BlackFriday rendering options set in your project configuration][config].
## Front Matter Format Specs
* [TOML Spec][toml]
* [YAML Spec][yaml]
* [JSON Spec][json]
[variables]: /variables/
[aliases]: /content-management/urls/#aliases
[archetype]: /content-management/archetypes/
[bylinktitle]: /templates/lists/#by-link-title
[config]: /getting-started/configuration/ "Hugo documentation for site configuration"
[content type]: /content-management/types/
[contentorg]: /content-management/organization/
[definetype]: /content-management/types/#defining-a-content-type "Learn how to specify a type and a layout in a content's front matter"
[headless-bundle]: /content-management/page-bundles/#headless-bundle
[json]: https://www.ecma-international.org/publications/files/ECMA-ST/ECMA-404.pdf "Specification for JSON, JavaScript Object Notation"
[lists]: /templates/lists/#ordering-content "See how to order content in list pages; for example, templates that look to specific _index.md for content and front matter."
[lookup]: /templates/lookup-order/ "Hugo traverses your templates in a specific order when rendering content to allow for DRYer templating."
[ordering]: /templates/lists/ "Hugo provides multiple ways to sort and order your content in list templates"
[outputs]: /templates/output-formats/ "With the release of v22, you can output your content to any text format using Hugo's familiar templating"
[page-resources]: /content-management/page-resources/
[pagevars]: /variables/page/
[section]: /content-management/sections/
[taxweight]: /content-management/taxonomies/
[toml]: https://github.com/toml-lang/toml "Specification for TOML, Tom's Obvious Minimal Language"
[urls]: /content-management/urls/
[variables]: /variables/
[yaml]: https://yaml.org/spec/ "Specification for YAML, YAML Ain't Markup Language"