FREE TOOL
Compare pixels
Free to use.
Overlay a design and a build, swipe between them, and see which pixels differ. Images stay in your browser.
The mockup or export that was signed off.
A screenshot of the page as it was built.
Add a design and a build to see where they differ.
Processed on your device. Nothing is uploaded.
How to use the
Compare pixels
Each step below matches what you see in the tool above.
Add both images
Drop the design export on the left and a screenshot of the build on the right, or choose the files.
Pick a view
Overlay fades the build over the design, Swipe splits them with a divider, Difference paints every changed pixel orange.
Read the score
The score shows the share of pixels that differ. Numbered boxes mark each changed region so you can point to it.
What people ask
before they use it
Short answers on how it works and what happens to your data.
No. Both images are read and compared in a background worker inside your browser tab. Nothing is sent to a server, and closing the tab discards them.
Found the mismatches?
Pin each one on the live page.
Free plan, no credit card. Reviewers never sign up.