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Compare Before and After Images

Upload the earlier and later versions, move the comparison slider, and inspect changed areas without sending the files to a server.

Interactive sliderLocal processingDifference heatmap
Image AOriginal
Image BModified

Upload both images to start comparing

JPEGPNGWebPGIFAVIFBMPHEICHEIF
Back to Compare Image Differences Online

Review what changed between two versions

This preset opens the visual-quality workflow with balanced sensitivity and noise suppression. The slider helps you inspect the same area in the before and after images.

The result also highlights decoded pixels whose color difference exceeds the selected threshold. It does not identify objects or explain why an edit changed.

How to compare before and after images

  1. 1

    Add the before image

    Choose the earlier or original version first.

  2. 2

    Add the after image

    Choose the edited, restored, compressed, or updated version second.

  3. 3

    Review and download

    Move the slider, adjust sensitivity if needed, and download the difference result.

Frequently asked questions

Are the images uploaded?

No. Supported images are decoded and compared locally in your browser.

Does this create one before-and-after collage?

No. This workflow compares two images interactively and produces a difference result; use the Before and After Photo Maker when you need one labeled composite image.

Is the comparison an AI similarity score?

No. It is a thresholded decoded-pixel comparison, not object recognition, SSIM, LPIPS, or semantic AI analysis.

Related image tools

Compare Compression Results

Inspect pixel changes between an original and compressed image.

Image Difference Heatmap

Highlight changed pixels and download the difference map.

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