hugo/docs/content/en/configuration/markup.md

title	linkTitle	description	categories	keywords	aliases
Configure markup	Markup	Configure markup.			/getting-started/configuration-markup/

Default handler

In its default configuration, Hugo uses Goldmark to render Markdown to HTML.

{{< code-toggle file=hugo >}} [markup] defaultMarkdownHandler = 'goldmark' {{< /code-toggle >}}

Files with ending with .md, .mdown, or .markdown are processed as Markdown, unless you've explicitly set a different format using the markup field in your front matter.

To use a different renderer for Markdown files, specify one of asciidocext, org, pandoc, or rst in your site configuration.

defaultMarkdownHandler	Renderer
asciidocext	AsciiDoc
goldmark	Goldmark
org	Emacs Org Mode
pandoc	Pandoc
rst	reStructuredText

To use AsciiDoc, Pandoc, or reStructuredText you must install the relevant renderer and update your security policy.

[!note] Unless you need a unique capability provided by one of the alternative Markdown handlers, we strongly recommend that you use the default setting. Goldmark is fast, well maintained, conforms to the CommonMark specification, and is compatible with GitHub Flavored Markdown (GFM).

Goldmark

This is the default configuration for the Goldmark Markdown renderer:

{{< code-toggle config=markup.goldmark />}}

Extensions

The extensions below, excluding Extras and Passthrough, are enabled by default.

Extension	Documentation	Enabled
cjk	Goldmark Extensions: CJK	✔️
definitionList	PHP Markdown Extra: Definition lists	✔️
extras	Hugo Goldmark Extensions: Extras
footnote	PHP Markdown Extra: Footnotes	✔️
linkify	GitHub Flavored Markdown: Autolinks	✔️
passthrough	Hugo Goldmark Extensions: Passthrough
strikethrough	GitHub Flavored Markdown: Strikethrough	✔️
table	GitHub Flavored Markdown: Tables	✔️
taskList	GitHub Flavored Markdown: Task list items	✔️
typographer	Goldmark Extensions: Typographer	✔️

Extras

{{< new-in 0.126.0 />}}

Enable deleted text, inserted text, mark text, subscript, and superscript elements in Markdown.

Element	Markdown	Rendered
Deleted text	~~foo~~	<del>foo</del>
Inserted text	++bar++	<ins>bar</ins>
Mark text	==baz==	<mark>baz</mark>
Subscript	H~2~O	H<sub>2</sub>O
Superscript	1^st^	1<sup>st</sup>

To avoid a conflict when enabling the "subscript" feature of the Extras extension, if you want to render subscript and strikethrough text concurrently you must:

1. Disable the Strikethrough extension
2. Enable the "deleted text" feature of the Extras extension

For example:

{{< code-toggle file=hugo >}} [markup.goldmark.extensions] strikethrough = false

[markup.goldmark.extensions.extras.delete] enable = true

[markup.goldmark.extensions.extras.subscript] enable = true {{< /code-toggle >}}

Passthrough

{{< new-in 0.122.0 />}}

Enable the Passthrough extension to include mathematical equations and expressions in Markdown using LaTeX markup. See mathematics in Markdown for details.

Typographer

The Typographer extension replaces certain character combinations with HTML entities as specified below:

Markdown	Replaced by	Description
...	…	horizontal ellipsis
'	’	apostrophe
--	–	en dash
---	—	em dash
«	«	left angle quote
“	“	left double quote
‘	‘	left single quote
»	»	right angle quote
”	”	right double quote
’	’	right single quote

Settings explained

Most of the Goldmark settings above are self-explanatory, but some require explanation.

duplicateResourceFiles

{{< new-in 0.123.0 />}}

(bool) Whether to duplicate shared page resources for each language on multilingual single-host sites. See multilingual page resources for details. Default is false.

[!note] With multilingual single-host sites, setting this parameter to false will enable Hugo's embedded link render hook and embedded image render hook. This is the default configuration for multilingual single-host sites.

parser.wrapStandAloneImageWithinParagraph

(bool) Whether to wrap image elements without adjacent content within a p element when rendered. This is the default Markdown behavior. Set to false when using an image render hook to render standalone images as figure elements. Default is true.

parser.autoDefinitionTermID

{{< new-in 0.144.0 />}}

(bool) Whether to automatically add id attributes to description list terms (i.e., dt elements). When true, the id attribute of each dt element is accessible through the Fragments.Identifiers method on a Page object.

parser.autoHeadingID

(bool) Whether to automatically add id attributes to headings (i.e., h1, h2, h3, h4, h5, and h6 elements).

parser.autoIDType

(string) The strategy used to automatically generate id attributes, one of github, github-ascii or blackfriday.

• github produces GitHub-compatible id attributes
• github-ascii drops any non-ASCII characters after accent normalization
• blackfriday produces id attributes compatible with the Blackfriday Markdown renderer

This is also the strategy used by the anchorize template function. Default is github.

parser.attribute.block

(bool) Whether to enable Markdown attributes for block elements. Default is false.

parser.attribute.title

(bool) Whether to enable Markdown attributes for headings. Default is true.

renderHooks.image.enableDefault

{{< new-in 0.123.0 />}}

(bool) Whether to enable the embedded image render hook. Default is false.

[!note] The embedded image render hook is automatically enabled for multilingual single-host sites if duplication of shared page resources is disabled. This is the default configuration for multilingual single-host sites.

renderHooks.link.enableDefault

{{< new-in 0.123.0 />}}

(bool) Whether to enable the embedded link render hook. Default is false.

[!note] The embedded link render hook is automatically enabled for multilingual single-host sites if duplication of shared page resources is disabled. This is the default configuration for multilingual single-host sites.

renderer.hardWraps

(bool) Whether to replace newline characters within a paragraph with br elements. Default is false.

renderer.unsafe

(bool) Whether to render raw HTML mixed within Markdown. This is unsafe unless the content is under your control. Default is false.

AsciiDoc

This is the default configuration for the AsciiDoc renderer:

{{< code-toggle config=markup.asciidocExt />}}

Settings explained

attributes

(map) A map of key-value pairs, each a document attribute. See Asciidoctor's attributes.

backend

(string) The backend output file format. Default is html5.

extensions

(string array) An array of enabled extensions, one or more of asciidoctor-html5s, asciidoctor-bibtex, asciidoctor-diagram, asciidoctor-interdoc-reftext, asciidoctor-katex, asciidoctor-latex, asciidoctor-mathematical, or asciidoctor-question.

[!note] To mitigate security risks, entries in the extension array may not contain forward slashes (/), backslashes (\), or periods. Due to this restriction, extensions must be in Ruby's $LOAD_PATH.

failureLevel

(string) The minimum logging level that triggers a non-zero exit code (failure). Default is fatal.

noHeaderOrFooter

(bool) Whether to output an embeddable document, which excludes the header, the footer, and everything outside the body of the document. Default is true.

preserveTOC

(bool) Whether to preserve the table of contents (TOC) rendered by Asciidoctor. By default, to make the TOC compatible with existing themes, Hugo removes the TOC rendered by Asciidoctor. To render the TOC, use the TableOfContents method on a Page object in your templates. Default is false.

safeMode

(string) The safe mode level, one of unsafe, safe, server, or secure. Default is unsafe.

sectionNumbers

(bool) Whether to number each section title. Default is false.

trace

(bool) Whether to include backtrace information on errors. Default is false.

verbose

(bool) Whether to verbosely print processing information and configuration file checks to stderr. Default is false.

workingFolderCurrent

(bool) Whether to set the working directory to be the same as that of the AsciiDoc file being processed, allowing includes to work with relative paths. Set to true to render diagrams with the asciidoctor-diagram extension. Default is false.

Configuration example

{{< code-toggle file=hugo >}} [markup.asciidocExt] extensions = ["asciidoctor-html5s", "asciidoctor-diagram"] workingFolderCurrent = true [markup.asciidocExt.attributes] my-base-url = "https://example.com/" my-attribute-name = "my value" {{< /code-toggle >}}

Syntax highlighting

Follow the steps below to enable syntax highlighting.

Step 1

Set the source-highlighter attribute in your site configuration. For example:

{{< code-toggle file=hugo >}} [markup.asciidocExt.attributes] source-highlighter = 'rouge' {{< /code-toggle >}}

Step 2

Generate the highlighter CSS. For example:

rougify style monokai.sublime > assets/css/syntax.css

Step 3

In your base template add a link to the CSS file:

<head>
  ...
  {{ with resources.Get "css/syntax.css" }}
    <link rel="stylesheet" href="{{ .RelPermalink }}" integrity="{{ .Data.Integrity }}" crossorigin="anonymous">
  {{ end }}
  ...
</head>

Then add the code to be highlighted to your markup:

[#hello,ruby]
----
require 'sinatra'

get '/hi' do
  "Hello World!"
end
----

Troubleshooting

Run hugo --logLevel debug to examine Hugo's call to the Asciidoctor executable:

INFO 2019/12/22 09:08:48 Rendering book-as-pdf.adoc with C:\Ruby26-x64\bin\asciidoctor.bat using asciidoc args [--no-header-footer -r asciidoctor-html5s -b html5s -r asciidoctor-diagram --base-dir D:\prototypes\hugo_asciidoc_ddd\docs -a outdir=D:\prototypes\hugo_asciidoc_ddd\build -] ...

Highlight

This is the default configuration.

{{< code-toggle config=markup.highlight />}}

{{% include "/_common/syntax-highlighting-options.md" %}}

Table of contents

This is the default configuration for the table of contents, applicable to Goldmark and Asciidoctor:

{{< code-toggle config=markup.tableOfContents />}}

startLevel

(int) Heading levels less than this value will be excluded from the table of contents. For example, to exclude h1 elements from the table of contents, set this value to 2. Default is 2.

endLevel

(int) Heading levels greater than this value will be excluded from the table of contents. For example, to exclude h4, h5, and h6 elements from the table of contents, set this value to 3. Default is 3.

ordered

(bool) Whether to generates an ordered list instead of an unordered list. Default is false.