Compare images pixel by pixel online

How image comparison works

Select two or more PNG, JPEG, GIF, TIFF or WebP files. Image Compare decodes them locally, checks their dimensions and compares corresponding pixels. The result reports whether the images are identical and how many pixels differ. Your image files stay in your browser and are not uploaded to Twelve Digital.

Useful examples

• Verify that an exported graphic matches its approved source file.
• Find small rendering changes between two screenshots of the same web page.
• Check whether image optimization changed pixels instead of only reducing file size.

Limits and interpretation

Pixel comparison is exact, not perceptual: a one-value color change counts as a difference even when it is hard to see. Files with different dimensions cannot be compared pixel for pixel. Animated images and metadata are not evaluated as a sequence or document; the tool compares the decoded raster frames available to the browser.

Frequently asked questions

Are my images uploaded?

No. Decoding and pixel matching run locally in your browser.

Why do visually identical images differ?

Compression, color conversion, transparency or browser decoding can change pixel values. The reported pixel count helps quantify that difference.