File Diff Checker

Upload two versions of the same file and see exactly what changed. Added lines are highlighted in green, removed lines in red. Perfect for comparing configuration files, JSON payloads, or code snippets completely offline.

Your files never leave your device. Processed locally. 100% private.

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How To Use File Diff Checker

Complete your task perfectly in just three straightforward steps.

1

Upload Original File

Upload the older or original version of your text file (JSON, XML, CSV, code, etc.).

2

Upload Modified File

Upload the newer or modified version of the same file to compare against the original.

3

View Differences

Instantly see exactly what changed. Added lines are highlighted in green, and removed lines in red. No data leaves your browser.

FAQ

Everything you need to know about the File Diff Checker.

Is this secure? Are my files uploaded to a server?

No files are uploaded anywhere. The diff checking process runs entirely locally in your browser. This makes it 100% secure for comparing sensitive configuration files, code, or private data.

What file types are supported?

Any plain text format is supported, including JSON, XML, YAML, HTML, Markdown, CSV, and source code files (.js, .ts, .py, etc.).

Can I view the diff side-by-side?

Yes, you can toggle between a Unified view (inline) and a Side-by-Side view depending on your preference.

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