Pixel Diff is the intuitive and powerful way to compare image files and PDF documents.

- Drag-drop and standard shortcuts to Load and Save images.
- Compares files of different image types, including PDF.
- Works with small and large images.
- Output image can be saved to disk at full resolution.
- Pixel Diff is a tool for professionals. It will not resample or rescale your images.

Various differencing methods to choose from:
-Difference Blending
-Mathematical Color Distance
-Difference Outlining to spot small differences
-Difference Masking
-Fader control to mix 2 images with a slider.
-Also includes Image Addition, Subtraction, and Multiply for performing advanced image operations! For example, Multiply a White Mask with another image to crop out the shape of the mask in that image.

Note when comparing PDF files, they are compared as images, so only the first page is used. Any visual changes will be detected, not just changes to text.

Thank you and enjoy!

Ratings and Reviews

4.0 out of 5
6 Ratings

6 Ratings

Cy1on ,

So Much Easier!

This app can tell differences in images- so when I think an image has been altered I just run it on the app. It is way easier, especially if you have to do this for work in large quantities. Saves tons of time.

DaveTheGnome ,

Simple, Excellent App

This is exactly what I was looking for. A simple, fast image comparison tool that tells me exactly how two images differ. I love the drag-and-drop feature and the ability to compare PDFs.

CaptainBagel ,

Nice tool for applying masks

I like the git style diff, but I've also been using it to modulate textures with alpha masks; its a lot faster than photoshop. Methinks this should be in Graphics and Design eh?


Christopher Meub
146 KB

OS X 10.8 or later, 64-bit processor



Age Rating


  • Family Sharing

    With Family Sharing set up, up to six family members can use this app.