Six things it does cleanly.
Side-by-side diff
Two panels, line-aligned. Additions, deletions, and changes are highlighted in place.
Real-time status
"Both are the same" or "Different" — flips the moment a character changes.
Character & line metrics
Both sides show character count and line count. Useful for length comparisons.
Sample data
Two sample passages preload on first launch — so you can see the diff in action without typing.
Clear button
Reset both panels in one click; great for moving on to the next pair.
State persistence
Both panels persist across sessions; yesterday's compare is still there.
Four moves to spot the change.
Paste the left
Original passage, version A, the "before".
Paste the right
Updated passage, version B, the "after".
Read the diff
Highlighted additions and deletions; status strip says "same" or "different".
Clear or copy
Reset both, or copy either side for the next round.
The work it actually does.
Code-review proxy
Compare two snippets without firing up a Git tool. The diff editor is the same one Git tools use.
Environment drift
Compare the same config across environments to spot the variable that drifted.
Two responses
Diff two HTTP responses to see exactly what changed when "intermittent" became reproducible.
Polishing prose
Compare a draft and a polish from AI Translate; see exactly what was rewritten.
Versioned strings
Diff two translation snapshots; understand what was added before re-publishing.
Documentation
Compare two versions of a doc page; the changes become a precise list.
Things people ask before they download.
Is the diff line-based or character-based?
Both: lines are the primary alignment, but within changed lines the editor highlights character-level differences.
What's "Both are the same" actually checking?
Exact equality after normalising line endings. Flip to "Different" the moment a character moves.
How big can the texts be?
The editor handles documents in the megabytes comfortably. Performance scales linearly; nothing freezes at "real" sizes.
Are line endings normalised?
Yes. CRLF and LF compare as identical so cross-platform copies don't show fake differences.
Is content stored remotely?
No. Everything lives in your local session. Nothing leaves the machine.
What if I want a JSON-aware diff?
Use the JSON Formatter's diff mode — it auto-formats both sides first, so cosmetic differences don't masquerade as real ones.