Markdown Linter

Paste a Markdown document and get a list of findings — heading hierarchy skips, mixed list markers, code fence issues, broken links and references, missing image alts, trailing whitespace, empty headings, and more. Findings are grouped by severity (error / warning / info) with the line number, the rule id, and a short message. Copy the findings as TSV or as a Markdown report. Pure client-side — nothing leaves your browser.

—

Findings

Errors
0
Warnings
0
Info
0
Lines
0
Headings
0
List items
0
Code blocks
0
Links
Images
0
Issues
    How to use this tool
    • Paste Markdown in the top textarea. Findings update live, sorted by line number.
    • Toggle severities to show only errors, only warnings, or everything including info-level hints.
    • Tweak the rule set — maximum heading-level jump, whether to require code-fence languages, whether to allow mixed - / * / + in the same list.
    • Copy the findings as TSV (spreadsheet-friendly) or as a Markdown report (PR-comment-ready).
    • All processing happens in your browser; the input is never uploaded.
    • The linter is intentionally approximate — it operates line by line and uses simple regexes, so it can produce false positives on unusual edge cases. Use it as a second pair of eyes, not as the source of truth.