Is my Markdown uploaded?

No. All parsing happens in browser JavaScript. Safe for internal docs and drafts.

How are anchor links generated?

Close to GitHub's slug rules: lowercased, spaces → hyphens, anything outside alphanumerics / hyphen / underscore / non-ASCII letters dropped. Example: 'API リファレンス' → '#api-リファレンス'. When the same heading appears multiple times, suffixes -1, -2, … are appended to disambiguate.

Are Setext-style headings (Heading\n=====) supported?

Not in this version — ATX only (`# Heading`). Convert Setext headings to ATX before pasting.

How are `#` lines inside code fences treated?

Anything inside ``` or ~~~ fences is skipped, so shell-style comments and Markdown headings written for documentation purposes don't leak into the TOC. Indented code blocks (4 spaces) aren't detected, so a `#` at the start of an indented line is still parsed as a heading.

If the page title is rendered separately (GitHub README, Notion, blog), leaving H1 out keeps the TOC clean. For long static sites that use H1 as a body section, include it. Default is off.

The anchor doesn't work on the real page

GitHub, Notion, Qiita, etc. each have slightly different slug generators. Inspect the rendered ` ` on the target site and adjust manually if needed.

Back to Developer

Markdown TOC — extract anchors from headings

Scan Markdown headings (#, ##, …) and emit a table of contents with GitHub-style anchor links. Toggle between nested and flat list, change the maximum heading level, and choose whether to include H1. Headings inside fenced code blocks are skipped automatically. Copy the Markdown or save as .md and paste it anywhere. Runs entirely in your browser.

developerMarkdowngenerate

How to use

Pick a list style (nested / flat), paste your Markdown, and press Generate TOC. The tool walks the document, picks up ATX-style headings (`# foo`, `## bar`, …), and emits Markdown links with GitHub-style anchors. Use the options to set the max heading level and decide whether to include H1. Lines starting with `#` inside fenced code blocks (```…```) are ignored automatically. Copy the result as Markdown or save as a .md file and paste it into your README / docs.

FAQ

Is my Markdown uploaded?: No. All parsing happens in browser JavaScript. Safe for internal docs and drafts.
How are anchor links generated?: Close to GitHub's slug rules: lowercased, spaces → hyphens, anything outside alphanumerics / hyphen / underscore / non-ASCII letters dropped. Example: 'API リファレンス' → '#api-リファレンス'. When the same heading appears multiple times, suffixes -1, -2, … are appended to disambiguate.
Are Setext-style headings (Heading\n=====) supported?: Not in this version — ATX only (`# Heading`). Convert Setext headings to ATX before pasting.
How are `#` lines inside code fences treated?: Anything inside ``` or ~~~ fences is skipped, so shell-style comments and Markdown headings written for documentation purposes don't leak into the TOC. Indented code blocks (4 spaces) aren't detected, so a `#` at the start of an indented line is still parsed as a heading.
Include H1 or not?: If the page title is rendered separately (GitHub README, Notion, blog), leaving H1 out keeps the TOC clean. For long static sites that use H1 as a body section, include it. Default is off.
The anchor doesn't work on the real page: GitHub, Notion, Qiita, etc. each have slightly different slug generators. Inspect the rendered `<h2 id="...">` on the target site and adjust manually if needed.

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