Edit YAML front matter in .md files — add, modify, delete fields with live preview. 100% local.
This tool runs 100% in your browser. All computation happens locally on your device — your input is never uploaded to any server. Results are for reference only.
A Markdown file with front matter is really two documents: a ----delimited YAML metadata block at the very top, then the Markdown body. Static-site generators (Hugo, Jekyll, Hexo) read the YAML for title, date, tags, draft and so on, then render the body. This tool parses that block with a YAML parser, exposes each key as a typed field (string, date, number, boolean, array, object, null), and re-serializes valid YAML on download — the body below the closing --- is preserved untouched.
Left: the raw file. The dashed --- fences mark the metadata region; everything after them is body. Right: each YAML key becomes an editable typed field, and the round-trip re-emits valid YAML (dates kept as yyyy-mm-dd so they are not re-parsed as timestamps).
Diego, a content engineer, has a half-finished blog post with front matter. He needs to flip it live and tidy its metadata before the next site build.
Edit YAML front matter in Markdown files. Add, modify, delete metadata fields with type detection. Live preview. Free, no signup.
This editor edits YAML front matter — the key: value block between --- markers at the top of Markdown files — without hand-editing YAML and risking indentation mistakes. Load a .md file and the tool parses the front matter into an editable form: existing fields show with detected types, new fields add with one click, and values edit as text, numbers, booleans, dates, or lists. A live diff previews exactly which lines change before you download the modified file, and the body below the front matter stays byte-identical. Everything runs locally, which suits the Jekyll, Hugo, and Hexo sites whose front matter often carries drafts and unpublished content.
Blog authors publishing via static site generators adjust titles, tags, and dates without YAML syntax errors blocking a build. Content teams standardizing metadata across posts — adding a consistent author field or category taxonomy — batch-edit fields and see each diff before saving. Technical writers maintaining documentation sets update version and last-reviewed stamps across many files. Anyone who has broken a Jekyll build with a stray space in front matter, then spent an hour finding it, adopts a form-based editor immediately.
(1) Upload or paste a Markdown file with front matter; the parser reads everything between the opening and closing --- delimiters. (2) Fields render as an editable list with type detection — strings, numbers, booleans, dates, and arrays each get an appropriate input. (3) Add, rename, or delete fields; reordering keeps the final YAML tidy. (4) Review the diff — original versus modified front matter side by side — then download the updated .md with body content untouched. Invalid YAML in the source is reported at load rather than mangled silently.
Front matter is the metadata header static site generators read to build routes and templates. Common fields across Jekyll, Hugo, and Hexo: title and description for page head data; date and lastmod controlling sort order and sitemap timestamps; tags and categories feeding taxonomy pages; draft: true excluding a post from production builds; slug and url overriding the default route; author and layout selecting templates. Type conventions matter: dates in ISO format (2026-08-15 or with time), lists either inline [a, b] or one - item per line, and strings with colons quoted. The classic build breakers are tabs instead of spaces, unquoted values containing colons, and inconsistent list indentation — precisely the mistakes a form-based editor structurally prevents. Keep custom fields aligned with your theme's expected names, and use lastmod updates deliberately: sitemap consumers treat it as a freshness signal.
YAML front matter is a metadata block at the top of a Markdown file, wrapped in --- delimiters. It contains key-value pairs like title, author, date, tags, and draft status. Static site generators like Hugo, Hexo, and Jekyll use it to manage post metadata.
Yes. Click the + Add field button at the bottom of the field list. Enter a field name, select a type (string, date, number, boolean, or array), and enter a value. The new field is automatically added to the front matter output.
The tool supports .md, .markdown, and .txt files up to 1MB. Files are processed entirely in your browser — no content is uploaded to any server.
Yes. The tool parses standard YAML front matter delimited by --- at the top of the file, which is the format used by Hugo, Hexo, Jekyll, Eleventy, and most static site generators.
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