Compare text differences
Paste two texts side by side and instantly see what changed. Additions, deletions, and modifications highlighted in real time.
Compare Texts
Comparison Complete
Here are the differences between your texts.
Comparison Summary
CompletedWhat this tool does not do
- Does not perform semantic or meaning-based comparison.
- Cannot compare files directly — paste text into the fields.
- Very large texts may take longer to process in-browser.
- Comparison is line-based with word-level highlighting within modified lines.
How It Works
Paste your texts
Add the original text on the left and the changed version on the right.
Click Compare
The LCS algorithm instantly computes the differences between both texts.
Review results
Green highlights are additions, red are removals, yellow are modifications.
Frequently Asked Questions
How does the text diff tool work?
Paste your original text on the left and the changed text on the right. The tool uses the LCS algorithm to compare lines and highlight additions (green), deletions (red), modifications (yellow), and unchanged text.
Can I compare code with this tool?
Yes. The tool works with any text including code, articles, or documents. It compares line by line and shows exactly what changed, with word-level highlighting.
Is my text uploaded to a server?
No. All processing happens entirely in your browser. Your texts never leave your device.
What does LCS mean?
LCS stands for Longest Common Subsequence. It is the standard algorithm used to find the minimum changes between two texts, showing only what was added or removed.
Can I compare more than two texts?
This tool compares two texts at a time. For each comparison, paste your pair of texts and click Compare.
Is GoToolly free?
Yes. No account, no limits, no payment.