Image A drop, click, or paste
Image B drop, click, or paste
tolerance 0 A B speed
Drop an image into each slot to begin.
no images yet

Different-sized images are compared over their overlapping area (aligned top-left); the non-overlapping margin counts as changed.

## Four ways to see a change

- Side by side — the plain view, A and B next to each other.
- Difference — unchanged pixels fade to grey; anything that differs lights up. Raise the tolerance to ignore tiny compression noise.
- Blink — flips between A and B on a timer, the astronomer's trick: a real change appears to jump while everything else sits still.
- Onion-skin — fades B over A with a slider, so you can dissolve from one to the other.

The readout shows how many pixels differ and what share of the frame that is — handy for “is this really the same export?” or catching a stray watermark.

## Good to know

- Comparison is pixel-exact on the decoded image. Two JPEGs that look identical can still differ by a few levels from re-compression — nudge the tolerance up to treat near-matches as equal.
- The diff PNG you export is the Difference view at full resolution.
- Everything is computed in your browser with a canvas; no image is ever sent anywhere.

Same shelf: Proof Desk compares text and Word docs · Photo Cleaner strips metadata · Scan Desk turns photos into clean scans.

Part of K-Engine Local Tools — free, privacy-respecting utilities that run on your device. View-source and you're reading the whole tool. MIT licensed · download the source.