Text diff compare — what changed between the two?

Paste two versions of anything — config files, transcripts, generated output — and see which lines were added and removed. Line-level comparison, fully local.

When line diff is the right tool

• Config drift — two environment exports that "should be the same".
• Generated output — re-run a generator and confirm only intended lines changed.
• Contract text — paste two versions of a message or doc to spot wording changes.

For structured data (API responses, JSON), use the response comparator — it understands fields, not just lines.

Is my text uploaded anywhere?

No. This page is a single static HTML file — comparison runs entirely in your browser. Disconnect from the internet after it loads.

Need the full toolbox?

This page is one tool from LocalDevToolbox — 15+ local developer tools: response comparator, context optimizer, stack trace analyzer and more.