Remove GFM-specific extensions and convert to strict CommonMark: tables to HTML, strikethrough to <del>, task lists normalized. Free.
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.
Paste GFM Markdown or drop a .md file
GFM-specific syntax is converted to CommonMark-compatible equivalents
Download the strict CommonMark output compatible with all CommonMark renderers
0 bytes uploaded. GFM to CommonMark 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.
~~strikethrough~~ → <del>strikethrough</del>, GFM pipe tables → HTML <table> blocks (CommonMark has no table syntax), autolinks are explicitly wrapped in angle brackets, and task list items are normalised.
CommonMark is the spec-compliant base that all major Markdown processors implement consistently. If your Markdown renders differently across tools, converting to strict CommonMark ensures consistent output.
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