Original Text
Modified Text
🔧 How It Works
Compare any two texts and spot every difference in seconds
Paste Both Texts
Enter your original text on the left and the modified version on the right
Click Compare
Hit 'Compare Texts' and the tool instantly highlights every difference
Review Differences
Green lines are additions, red lines are removals — copy or download the result
Frequently Asked Questions
Everything you need to know about comparing text online
Do I need to sign up or log in to use this tool?
No. All QuickTextTools are completely free to use online with no login, signup, or account required.
How does the text comparison work?
The tool uses a Longest Common Subsequence (LCS) algorithm to compare texts line by line. It highlights lines that were added (green), removed (red), or unchanged (gray).
Can I compare code files with this tool?
Yes! The diff checker works perfectly for comparing code, config files, JSON, HTML, and any plain text. It preserves all indentation and formatting.
Is my text data stored or sent to a server?
No. All comparison happens entirely in your browser using JavaScript. Your text never leaves your device, making it completely private and secure.
What is the maximum text size I can compare?
The tool handles large texts efficiently. For very large documents (10,000+ lines), processing may take a moment but will complete accurately.
Can I download the diff result?
Yes. You can download the diff output as a plain text file with standard unified diff format (+/- prefixes) using the Download button.
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