File Diff Checker
Upload two files and compare changes like an IDE — side-by-side or unified diff.
Drop a file here
or click to browse · text & code files
Drop a file here
or click to browse · text & code files
About File Diff Checker
What is a File Diff Checker?
A File Diff Checker compares two versions of a file and highlights what changed — the same way your IDE or Git shows a diff. Upload an original file and a modified file to see additions (green), deletions (red), and unchanged lines side-by-side or in a unified view.
How to use it:
1. Drop or select the original file on the left.
2. Drop or select the modified file on the right.
3. Review the diff. Switch between Side by side and Unified views — just like VS Code or JetBrains.
Common use cases:
Review code before a commit, compare config or script revisions, check what an editor changed in a document, or verify patch results without opening a full IDE.
Frequently Asked Questions
Are my files uploaded to a server?
No. Files are read entirely in your browser with the FileReader API. Nothing is uploaded, stored, or sent to our servers — comparison stays private on your device.
How is this different from the Text Diff Checker?
Text Diff is for pasting text. File Diff lets you upload two files and uses an LCS-based alignment (like an IDE) so inserted or deleted lines do not throw off the rest of the comparison.
What file types are supported?
Any plain-text or source file — for example .ts, .js, .py, .json, .md, .css, .html, .yml, .liquid, and similar. Binary files are rejected. Files are limited to 2 MB and 8,000 lines for browser performance.
What do side-by-side and unified views mean?
Side-by-side shows original and modified files in two columns (IDE compare view). Unified stacks removals (−) and additions (+) in one list, similar to a Git patch.