Side-by-side image comparison tool. Compare before and after edits. Free online — no signup required.
Compare two images with slider, side-by-side, overlay, or difference view.
Drop two images here
or click to browse · upload 2 images to compare
Compare two images using side-by-side panels, an interactive slider that wipes between A and B, or an onion-skin overlay with adjustable opacity. The tool aligns images at matching pixel coordinates so any difference in framing is obvious. Useful for evaluating compression settings before committing to a quality level, verifying that an export is identical to the source, presenting before-and-after retouching to a client, comparing different camera lenses or filters on the same scene, and double-checking that an upscale or denoise actually improved the image rather than introducing artefacts.
Use the slider mode for compression and quality comparisons — the eye is much better at detecting small differences when one panel transitions smoothly into another than when both are static. Use side-by-side for framing or composition comparisons where the two images differ structurally. Use onion-skin (overlay with opacity) for evaluating subtle color or exposure changes in retouching. For a numerical similarity score rather than a visual comparison, use the dedicated Image Similarity tool instead.
Upload image A and image B
Drop two images of any supported format. They don't need to be the exact same dimensions, but matching dimensions make spotting differences easier.
Pick a comparison mode
Choose Side by Side for framing comparisons, Slider for compression and quality checks, or Onion Skin for subtle retouching evaluations.
Adjust the view
Drag the slider, change overlay opacity, or zoom into a region. Both images respond together so you can pixel-peep specific areas.
Capture or export
Take a screenshot of the comparison or export the side-by-side as a single combined image to share with collaborators.
Your images are processed entirely in your browser. They are never uploaded to any server. Once you close the tab, all data is gone. No tracking, no storage, no cookies for your files.
No, but matching dimensions make differences much easier to spot. Mismatched images are scaled to share a comparison frame; their relative pixels do not align exactly.
Compare is a visual side-by-side tool for human evaluation. Similarity returns a numerical similarity percentage based on pixel comparison or perceptual hashing. Use Compare when you need to see; Similarity when you need a number.
Yes. Export combines both images into one side-by-side composite, useful for sharing or embedding into a report or blog post.
Yes. Each image's file size is shown alongside the comparison, so you can see the size difference and decide whether it's worth the visual quality difference.
This tool focuses on two-image comparisons. For multi-way comparison, generate side-by-side outputs in pairs and stitch them with the Stack tool.