Markdown Diff Checker
Compare two markdown versions line by line
Original Markdown
Modified Markdown
Diff Report
Markdown Diff Examples
Compare two Markdown versions. Example:
Example: Plan with added item
Modified Markdown (added Item C):
Diff report output:
Click the Sample button above to load more examples into the editors.
What Is the Markdown Diff Checker?
The Markdown Diff Checker compares two Markdown versions and shows line-by-line differences. Paste the original in the left panel and the modified version in the middle; the right panel displays the diff report. The CommonMark spec defines Markdown syntax.
This tool runs entirely in your browser. Nothing is sent to a server. Use Sample to load example diff data. For formatting or validation, use Markdown Formatter or Markdown Validator. For linting, use Markdown Linter.
How to Use This Tool
Paste Original and Modified
Paste the original Markdown in the left panel and the modified version in the middle. Use Sample to load example content. Use Clear to reset both.
Review the Diff Report
The right panel shows added, removed, and changed lines. Use this to review edits, track changes, or prepare patch notes.
Copy or Download Report
Use Copy or Download to save the diff report. For TOC generation from either version, use Markdown TOC Generator.
When the Markdown Diff Checker Helps
When comparing drafts, reviewing PRs on GitHub or GitLab, or tracking doc changes, the diff shows exactly what changed. The GFM spec defines Markdown. Great for documentation workflows, README updates, and content review. For linting style issues, use Markdown Linter. For conversion, use Markdown to HTML.
Frequently Asked Questions
Is my data private?
Yes. Diffing runs entirely in your browser. No data is sent to any server.
How is the diff computed?
The tool compares lines between the two versions. Added, removed, and modified lines are highlighted in the report.
Can I upload files?
This tool uses paste input. Copy content from your files and paste into each panel. For single-file tools, use Markdown Formatter or Markdown Linter.
Does it support large documents?
Large documents may be slower to diff. There is no hard limit, but very long files may affect performance.
Can I export as patch?
The report shows the diff. For a unified diff or patch format, you may need a separate diff tool or git diff.