Reference image
Local image
Reference preview
Image Compare
See where two images change.
Compare screenshots, design revisions or photographs. Review them together, reveal one over the other, and download a complete pixel-change mask.
Processed on your device · no uploads or saved image historyCandidate image
Local image
Candidate preview
Comparison settings
Visible mode compares appearance on black and white backgrounds. RGBA includes hidden channel differences in the decoded pixels.
0 detects every nonzero delta. A pixel changes only when its delta is greater than this value.
Reduction is explicit and never enlarges an image. The actual analysis dimensions appear in the report.
Still PNG, JPEG and WebP · up to 20 MiB and 32 million original pixels per file. Analysis supports up to 4096 pixels per edge and 8,388,608 pixels. Animation is not compared.
Comparison result
Magenta marks changed pixels- Changed pixels
- Pixels compared
- Maximum delta
- Changed bounds · x, y start at 0
Understand the difference
A pixel comparison
This compares sRGB 8-bit pixels decoded by your browser. It does not measure semantic similarity or prove the original files are identical. Use File Checksum to compare original bytes.
Transparency is explicit
Visible mode checks colours composited on black and white. Fully transparent hidden colour is ignored. RGBA mode checks all four decoded channels. Browser decoding can discard or round colour information.
Your originals stay yours
Rotation metadata is applied consistently in memory. Your selected files are never overwritten. Changing an image or analysis setting clears old exports; Compare images always starts a new analysis.
What if image dimensions differ?
You can review the two previews together, but no pixel count or mask is invented. Prepare matching dimensions in Image Studio, or choose the explicit reduction policy when appropriate. The tool never silently stretches, crops or pads an image.
What does the PNG contain?
The complete change mask at the reported analysis dimensions: changed pixels are opaque magenta, unchanged pixels are transparent. Small changes are enlarged in the scaled mask preview so they remain visible. Preview scaling does not reduce or enlarge the changed pixels in the PNG. The text and JSON reports include filenames, settings, dimensions, changed pixels and bounds.
Browser and privacy limitations
Some browser privacy settings alter canvas pixels. If a known calibration fails, the tool stops without producing a comparison. Available image memory also varies by device; try smaller images or explicit reduction when needed.