DEV3 Free Text Diff Checker — Source Code (React + Tailwind)

Source code of the DEV3 Text Diff Checker, a text comparison tool with side-by-side and inline views, line or word granularity and ignore-whitespace and ignore-case options.

Free download: sign in to any DEV3 account and click Download ZIP. Try it live: https://dev3.tech/tools/text-diff-checker shows the finished tool running.

What is in the download

• A standalone Vite + React + TypeScript + Tailwind CSS project: src/tool holds the tool, shared pieces sit beside it
• package.json with exact versions plus a lockfile, so npm ci works
• README.md (run, build, embed in Next.js or plain React) and an MIT LICENSE

What the code does

• LCS diff with common prefix/suffix trimming
• Word-level highlights inside changed lines
• Added/removed counters and identical notice
• Safe fallback for very large inputs

Tech stack

React 19, TypeScript, Vite, Tailwind CSS 4.

Install and customise

The How to install and How to use tabs list the steps. In short: unzip, npm ci, npm run dev, then copy the tool folder into your own app if you want to embed it.

Good to know

• A browser-only tool: there is no backend or database in the code.
• Very large inputs use a coarse replace-all diff to stay responsive.