Documentation Lint Preview
Check how Markdown looks under different rules. Compare previews and find lines that may display differently in another editor.
Can Markdown render differently across documentation systems?
Yes. Compare the CommonMark, Extended Markdown, or Plain formatting presets to see rendering differences. A line-numbered report flags selected extension syntax and common unsupported constructs for manual review.
Your document
On your deviceDocument preview
A clear view of your words.
Run the tool to preview the document and prepare your export.
Three simple steps
How to use Documentation Lint Preview
Paste or open the Markdown document you want to check.
Choose two rendering presets and compare their previews.
Review line-numbered findings and export the comparison report.
Common questions
Good to know
Understand the result.
Keep the original.
Is this tool free, and are my files uploaded?
This tool is free with no account required. The work happens in your browser. Your input and files are not sent to a processing server.
What are the limits and details?
These are explicitly defined local presets, not exact emulations of GitHub, a CMS, or every Markdown implementation. Lint findings are advisory; raw HTML, footnotes, task boxes, and math extensions are not enabled.
Limits: 120,000 Markdown characters. Rendering runs on this device with a 30-second limit.