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Image Compare

Put two versions of a picture next to each other and see exactly what changed, down to a single pixel.

Runs in your browser · No uploads

First image (before)

No image yet

Second image (after)

No image yet

Drop an image on each box, or paste one with Ctrl+V (it goes into the first empty box). Your images stay on your device.

  • Nothing leaves your device
  • No server-imposed size limits
  • No sign-up, no watermark
  • Free

How to compare two images

  1. Choose or drop the first and the second image (or paste them).
  2. Slide the divider, view them side by side, or switch to Differences.
  3. Read how many pixels differ, and download the difference picture if you need it.

Uses

  • Check what a compressor or converter changed, and whether you can see it.
  • Compare design versions, screenshots before and after a change, or two exports.
  • Spot retouching between an original and an edited photo.

The numbers

  • A pixel counts as changed when one of its color values differs by more than the threshold (0 to 255).
  • PSNR (peak signal-to-noise ratio): above about 40 dB differences are very hard to see; below 30 dB they usually show.
  • Images of different sizes are compared after scaling the second one to the first one's size.

Frequently asked questions

Can it compare PDFs or videos?

Not directly. Save the pages or frames as images first (PDF to JPG, Video Thumbnail Extractor), then compare them here.

Are my images uploaded?

No. Everything happens in your browser, and the page is blocked from uploading anything.