Compare images pixel by pixel — free & private
Upload two versions of an image and see exactly what changed — highlighted in red. Nothing is uploaded.
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What is image diff?
An image diff computes the difference between two versions of an image, pixel by pixel, and highlights the changed areas. It's how designers and developers verify that a change landed exactly where expected.
The tool reports the percentage of changed pixels and produces a heatmap you can download. Tolerance lets you ignore noise from JPEG artifacts.
How to image diff
- Add Image A (original) and Image B (changed).
- Adjust the tolerance to filter out noise.
- Review the heatmap and the change percentage.
- Download the diff image if you need to share it.
Frequently asked questions
What does the percentage mean?
The share of pixels that differ beyond your tolerance — 0% means the images are identical.
Can images be different sizes?
Yes — both are aligned to a shared canvas before comparing.
Is this done on a server?
No. The comparison runs entirely in your browser.
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