UI-driven YAML frontmatter generator for static site generators — Gatsby, Next.js, Hugo, Astro. Fill in fields and prepend to your Markdown. Free, browser-based.
Free is enough for most one-off jobs. Pro raises the file and batch caps; Pro + Media unlocks GB-scale streaming and unlimited duration.
Larger files supported on Developer (5 GB CSV) and Enterprise (unlimited). All processing happens in your browser — files never reach a server.
Fill in the frontmatter fields: title, date, slug, tags, description, and draft status
Optionally paste your existing Markdown in the body area
Download the complete .md file with correctly formatted YAML frontmatter prepended
0 bytes uploaded. Frontmatter Builder runs entirely in your browser using JavaScript. Your markdown — including any secrets, PII, or proprietary content — never leaves your device. No data is sent to any server.
The output uses standard YAML frontmatter delimited by --- which is compatible with Gatsby, Next.js (MDX), Hugo, Astro, Jekyll, Eleventy, and VitePress.
Yes — the 'Custom fields' section lets you add arbitrary key: value pairs to the frontmatter block for any SSG-specific metadata.
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