Drop the reference imageor paste an image
Local visual QA · Pixelmatch · no uploads
Compare two images beyond the slider
Drop an original and a result. Inspect the visible change, measure changed pixels and export an evidence-grade diff — entirely in your browser.
Drop the image to compareor paste an image
JPEG, PNG, WebP, AVIF, GIF and BMP · up to 50 MB each
VISUAL QA
Choose how to inspect the change
Press and hold the image or Space to reveal Image B.
Difference receipt
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Large images are analyzed on a proportional grid up to 2048 px / 4 MP to protect browser memory. Originals are never changed.
Both images and the generated diff stay on this device.
PIXELMATCH · WORKER · LOCAL
A visual check and a measurable answer
A slider shows where something changed. Pixelmatch adds a perceptual difference map, anti-alias handling and repeatable numbers, so compression, retouching and rendering decisions do not rely on memory.
Five inspection modes
Swipe, opacity, press-to-flicker, side-by-side and a downloadable pixel diff reveal different classes of change.
Honest normalization
Different dimensions are never silently ignored. Choose fit, crop or stretch and see the exact analysis grid.
Worker-isolated analysis
Decoding and millions of pixel comparisons run away from the interface, with a timeout for pathological inputs.
Image comparison questions
Is this a similarity or plagiarism detector?
No. It compares two aligned raster renderings. It does not search the web, recognize objects or decide whether images share authorship.
Why can two visually similar images show changed pixels?
Compression, color profiles, resampling and anti-aliasing can alter pixel values. Raise the threshold or exclude anti-aliasing to focus on larger visible changes.
What does PSNR mean?
It is a pixel error signal in decibels: higher means closer, and identical pixels are reported separately. It is useful evidence, not a universal judgment of visual quality.
Are my images uploaded?
No. Files are decoded, normalized and compared in a browser Worker. Network requests may still load the application code, but none carries your image files.