HTML差分ツール オンライン
HTMLファイルやスニペットをオンラインで比較し、差分を瞬時に検出します。
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What Is HTML Diff?
HTML Diff is a free online tool that compares two HTML files or snippets line by line and highlights every addition, deletion, and modification. Use it to review template changes, compare email HTML, track UI markup edits, or diff any HTML between deployments.
How to Use HTML Diff
- Paste your original HTML into the left panel.
- Paste the modified HTML into the right panel.
- Optionally enable Normalize to collapse whitespace for a cleaner diff.
- Click Compare to see the highlighted differences.
- Use Split or Unified view to review changes.
Features
- Line-by-line HTML comparison
- Normalize option to ignore indentation and whitespace changes
- Split and unified diff views
- Works with full pages and HTML snippets
- Added / removed line counters
- Copy diff result to clipboard
FAQ
What does the Normalize option do?
Normalize collapses multiple spaces and tabs into single spaces and removes blank lines before comparing. This eliminates indentation-only changes and makes the diff focus on meaningful content differences.
Is my HTML sent to a server?
No. HTML Diff runs entirely in your browser. Your content is never uploaded to any server.
Can I compare full HTML pages and snippets?
Yes. Paste a full HTML document with doctype and head, or just a fragment like a nav bar or form — both work the same way.