Developer Tools

Diff Checker Online

Compare two text blocks and find the differences easily.

Added lines Removed lines Changed lines

Compare Text

What is a Diff Checker?

A diff checker is an online comparison tool that helps you compare two blocks of text, code, or content and quickly identify what has changed. It highlights added, removed, modified, and unchanged lines so you can review differences faster.

Line-by-line diff

Clearly shows every addition, removal, and modification between two text versions.

Works with code too

Paste HTML, JavaScript, Python, or any other code — the diff works for all text formats.

Useful for everyone

Developers, writers, students, and editors can all benefit from comparing text revisions quickly.

How to compare text online

1. Paste original text

Paste your original text or code into the left input box.

2. Paste changed text

Paste the modified version into the right input box.

3. Click Compare

Hit "Compare Text" to instantly see differences highlighted by color.

Frequently asked questions

A diff checker compares two text blocks and shows added, removed, changed, and unchanged lines. Each type is color-coded for easy review.

Yes. You can paste any code — HTML, JavaScript, Python, PHP, etc. — into both boxes and compare changes line by line.

Yes, FunXTools Diff Checker is completely free to use with no signup, no ads, and no limits.

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