What is a Text Diff Tool?
A text diff tool compares two texts line by line or character by character, visually highlighting added, removed, and changed sections. It is essential for developers reviewing code changes and for writers or editors comparing previous and current versions of documents.
This tool uses the LCS (Longest Common Subsequence) algorithm for precise character-level difference detection, supporting both unified and side-by-side views. Flexible options like ignore whitespace and ignore case allow purpose-specific comparisons.
Key Features
Unified / Side-by-Side Toggle
Freely switch between Unified and Side-by-Side views to compare text in your preferred layout.
Character-Level LCS Diff
Uses the LCS algorithm for character-level comparison to highlight exact change points.
Scroll Synchronization
In side-by-side mode, both panels scroll together so you can easily compare the same position.
Copy Results & Flexible Options
Copy comparison results to clipboard and use ignore whitespace/case options as needed.
How to Use
- Enter Original Text — Paste the original text in the left input area.
- Enter Text to Compare — Paste the text to compare in the right input area.
- Set Options — If needed, select ignore whitespace or ignore case options.
- View Results — Check the automatically generated comparison results showing added (green) and removed (red) lines.
Use Cases
Code Review
Compare code before and after a pull request to quickly identify changed logic, new functions, and deleted code.
Document Version Comparison
Compare previous and current versions of contracts, reports, or proposals to accurately identify changes.
Translation Verification
Compare original and translated text side by side, or compare translation revisions to catch omissions or errors.
Config File Change Tracking
Compare before and after changes in server configs or environment files to detect unintended modifications.
Frequently Asked Questions
Q. What is a text diff tool?
A text diff tool finds and visually displays the differences between two texts line by line. It's widely used in programming to review code changes and in document work to compare versions.
Q. Is my text data safe?
Yes, all comparison operations are processed within your browser. The text you enter is not sent to any server, and all data is deleted when you close the page.
Q. Are there any limits on text size?
There are no specific limits, but very large texts (tens of thousands of lines) may process slower depending on your browser's performance.
Q. What is the difference between Unified and Side-by-Side view?
Unified view shows changes in a single flow, making it easier to understand the overall context. Side-by-Side view displays the original and modified text next to each other for intuitive comparison.
Privacy Notice
All text you enter is processed entirely in your browser and is never sent to any server. Data is completely deleted when you close the page. Feel free to compare sensitive code or documents with confidence.