All Tools / Text Tools / Compare Two Files
Compare Two Files
Spot the differences between two documents with line-by-line diff highlighting.
How It Works
The diff is computed using the Longest Common Subsequence (LCS) algorithm, the same approach used by Unix diff. Lines present only in A are shown in red, lines present only in B are shown in green, and shared lines are shown as-is. Toggle “Show changes only” to hide unchanged lines. Nothing leaves your browser.
How to Compare Two Text Files
01
Add the Files
Paste or load the first and second versions of your text.
02
Review Differences
Scan the side-by-side comparison for inserted, removed, or changed lines.
03
Copy What You Need
Use the comparison to verify revisions or combine the correct content.
Line-by-Line Text Comparison
The comparison splits each input into lines, matches common content, and marks additions and removals so changes are easy to inspect.
Both inputs remain in your browser tab. The tool does not upload or log your documents.
Frequently Asked Questions
What files can I compare?
You can compare plain text, code, Markdown, JSON, and other text-based content.
Does comparison change either file?
No. The tool only displays differences and leaves your original content unchanged.
Can I compare large documents?
Yes, although very large files may take longer because the comparison runs in browser memory.
Is confidential text private?
Yes. The comparison runs locally and your documents are not sent to a server.
Related Daily Utilities