Online Code Diff Tool
Compare code snippets or entire files side by side with full syntax highlighting for JavaScript, TypeScript, Python, Go, Rust, SQL, YAML, and more.
Open the Tool — Free & InstantYour data never leaves your browser
No server processing
All diffing runs locally in your browser using JavaScript. Zero data transmitted.
No logging or storage
We do not store, log, or read your content. Nothing is saved anywhere.
Safe for sensitive content
Confidential code, config files, API keys — safe to compare here.
PII detection on share
Before any share link is generated, your content is scanned for emails, API keys, and tokens — with options to redact or encrypt.
Features
- ✓Syntax highlighting for 13 languages
- ✓JavaScript, TypeScript, Python, Go, Rust support
- ✓HTML, CSS, SQL, YAML, Markdown support
- ✓Side-by-side and unified diff views
- ✓Character-level change highlighting within lines
- ✓Download diff as .patch or HTML file
- ✓Shareable links — send any code diff via URL
- ✓100% in-browser, code never sent to a server
Frequently Asked Questions
How do I compare two code files online?
Paste the original code in the left panel and the new code in the right panel. Select the language from the dropdown for syntax highlighting. Changed lines are instantly highlighted.
Which programming languages are supported?
JavaScript, TypeScript, Python, JSON, HTML, CSS, Shell/Bash, Go, Rust, SQL, YAML, and Markdown. Select the language from the toolbar to enable syntax highlighting.
Can I download the diff output?
Yes. Click the Download button in the toolbar to export the diff as a .patch file (standard unified diff format) or as a styled HTML file.
Is this the same as git diff?
The output is similar to git diff — you can view in unified mode which shows + and − markers just like git. You can also download a .patch file that is compatible with git apply.
Is my code kept private?
Yes. All diffing runs in your browser. Your code is never uploaded, logged, or stored. Safe to use with proprietary or unreleased code.