Markdown Frontmatter Extractor

Pull frontmatter out of a Markdown file and convert between YAML, JSON, and TOML.

Output format

Summary — What Free Markdown Frontmatter Extractor Does

What This Free Tool Is

Free Markdown Frontmatter Extractor pulls the YAML, TOML, or JSON frontmatter block out of a Markdown file, parses it into structured data, and lets you output the result in any of the three formats. The body is extracted separately so you can manipulate or migrate both independently.

Privacy: This tool runs entirely in your browser. Your text is never uploaded, logged, or cached. Close the tab and it's gone. Verify in DevTools → Network: zero requests fire.

Why It's Free (And How We Keep It Free)

Every static-site migration eventually needs a frontmatter converter, and hand-writing one is a trap of edge cases. The parser runs 100% in your browser, and your content never leaves your device.

Table of Use

At-a-Glance Reference

InputOutputTypical sizeSpeedLogin needed
Markdown (.md) with frontmatterParsed frontmatter (YAML/JSON/TOML) + bodyAny post size< 10 msNo

Markdown Frontmatter Extractor Features

Here's what this free tool does in detail — every feature is built to solve real problems, runs entirely in your browser, and is free forever.

YAML, TOML, and JSON Detection

Automatically detects and parses all three frontmatter flavors: YAML (--- delimiters — Jekyll, Hugo, Astro, 11ty, Docusaurus), TOML (+++ delimiters — Hugo, Zola), and JSON (;;; delimiters — rare but used by some SSGs). The detected source format is shown as a chip next to the character count so you know what shape your file has.

For a deeper Markdown structure analysis, use the Free Markdown to JSON (AST) tool.

Convert Between Formats

Pick the output format (YAML, JSON, or TOML) with a radio toggle. Migrate from Jekyll's YAML to Hugo's TOML, from TOML back to YAML for Astro, or export to JSON for a static API. The extractor round-trips flat key/value pairs, simple arrays, inline arrays, multi-line lists, booleans, numbers, and nulls.

For bulk site migrations that also need link rewrites, use the Free Obsidian Wikilinks to Markdown.

Body Extracted Separately

The post body (everything after the closing frontmatter delimiter) is extracted into its own panel so you can copy it without the metadata. Useful when you're moving content to a CMS that stores frontmatter in a database and only needs the markdown body, or when you're running the body through a formatter or linter.

Lightweight, Dependency-Free Parser

The frontmatter parser handles 95% of real-world shapes without pulling in a 100 KB YAML library. Flat keys, arrays (inline and multi-line), quoted strings, booleans, numbers, and nulls all work. For exotic shapes (deeply nested maps, anchors, tags), the output falls back to strings gracefully.

Once you have clean frontmatter, pair with the Free Markdown Formatter to normalize the body too.

How To Use Free Markdown Frontmatter Extractor

Step 1 — Paste a Markdown file

A Jekyll, Hugo, Astro, 11ty, or Docusaurus post with a frontmatter block at the top.

Step 2 — Pick an output format

YAML, JSON, or TOML — convert between any of the three.

Step 3 — Copy frontmatter or body

Grab the parsed frontmatter for a script, or grab the body for a migration.

Who Can Use This Tool

Static site maintainers

Audit frontmatter across hundreds of posts during a migration from Jekyll to Hugo or Astro.

Content engineers

Pipe frontmatter from existing posts into a headless CMS without hand-rewriting metadata.

Blog authors

Switch static site generators without losing post metadata.

Developers building plugins

Test frontmatter parsing without building a local dev environment.

Migration scripts

Copy-paste spot checks to verify a batch migration is parsing frontmatter correctly.

Frequently Asked Questions

Is this frontmatter extractor free?

Yes. Free forever, no account required.

What formats does it detect?

YAML (---), TOML (+++), and JSON (;;;).

Can I convert between formats?

Yes. Pick the output format with the radio toggle to round-trip YAML ↔ JSON ↔ TOML.

Does it handle nested data?

Flat keys, arrays, booleans, numbers, and nulls all work. Deeply nested maps fall through as strings.

Is my content uploaded?

No. Runs 100% in your browser.

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