Diff Checker is a lightweight Chrome extension that instantly highlights differences between any two blocks of text, code, JSON or even two open tabs, and can generate an AI-powered summary on demand. All comparisons run locally; nothing leaves your browser.

Hey Product Hunters! I built Diff Checker because I was tired of copy-pasting snippets into external sites just to spot tiny changes - or waiting forever for large diffs to load. What it does: * One-click diff for text, code, JSON or the content of two active tabs. * Optional AI summary (plug in your own OpenAI key; your data stays local unless you enable this). * Privacy-first: all comparisons run in-browser, no servers, no tracking. * Tiny footprint (<500 KB) and works offline. If you live in VS Code or review docs all day, give it a spin and let me know what saves you the most time. Feature ideas and bug reports are gold—drop them below! 🔗 Install: Chrome Web Store Thanks for checking it out - excited to hear your feedback!

Congrats, Pavel! Diffing the content of two open tabs is the feature I didn't know I wanted — pasting snippets into some random diff site is exactly the habit worth killing. And nice that the AI summary is opt-in with your own key rather than baked in. 🎉

Good luck with your launch

Bravo, Pavel! Looks very useful

Good luck with your launch

Bravo, Pavel! Looks very useful

Diff Checker

Instant AI diff for text, code & JSON right in Chrome

Instant AI diff for text, code & JSON right in Chrome