remark-gfm

Install remark-gfm via npm for Node.js (version 16+). Note that this package is ESM only.

In Deno, use esm.sh:

import remarkGfm from 'https://esm.sh/remark-gfm@4'

In browsers, use esm.sh with the ?bundle query parameter:

<script type="module">
  import remarkGfm from 'https://esm.sh/remark-gfm@4?bundle'
</script>

npm install remark-gfm

By default, remark-gfm supports strikethrough with a single tilde (~text~) to match GitHub's behavior. To disable this and only support the standard GFM double tilde (~~text~~), set singleTilde: false in the options.

const file = await unified()
  .use(remarkParse)
  .use(remarkGfm, {singleTilde: false})
  .use(remarkRehype)
  .use(rehypeStringify)
  .process('~one~ and ~~two~~')

console.log(String(file)) // Yields: <p>~one~ and <del>two</del></p>

To enable GitHub Flavored Markdown (GFM) support—including autolink literals, footnotes, strikethrough, tables, and tasklists—add remarkGfm to your unified processor pipeline using .use(remarkGfm).

This plugin handles parsing and serializing GFM syntax but does not handle the conversion to HTML; that is typically performed by remark-rehype and rehype-stringify.

import rehypeStringify from 'rehype-stringify'
import remarkGfm from 'remark-gfm'
import remarkParse from 'remark-parse'
import remarkRehype from 'remark-rehype'
import {read} from 'to-vfile'
import {unified} from 'unified'

const file = await unified()
  .use(remarkParse)
  .use(remarkGfm)
  .use(remarkRehype)
  .use(rehypeStringify)
  .process(await read('example.md'))

console.log(String(file))

When formatting markdown tables, remark-gfm uses the stringLength option to determine the visual width of cells. This is useful for correctly aligning tables containing full-width characters (like Chinese characters) or emojis, which standard .length properties may miscalculate.

Pass a function like string-width to the stringLength option to ensure accurate alignment.

import {remark} from 'remark'
import remarkGfm from 'remark-gfm'
import stringWidth from 'string-width'

const input = `| Alpha | Bravo |
| - | - |
| 中文 | Charlie |
| 👩‍❤️‍👩 | Delta |`

const file = await remark()
  .use(remarkGfm, {stringLength: stringWidth})
  .process(input)

console.log(String(file))

The remarkGfm plugin accepts an optional options object to configure its behavior.

The remarkGfm plugin adds support for GitHub Flavored Markdown (GFM) extensions to a unified or remark processor. This includes support for:

• Autolink literals
• Footnotes
• Strikethrough
• Tables
• Tasklists

To use it, import the default export and pass it to the .use() method of your processor. You can optionally provide a configuration object.