Free Web ToolsCompare two images with a slider, overlay, or pixel diff. Exact diff requires matching dimensions.
You can also drag and drop files here.
Files are processed in this browser. File contents and names are never uploaded or saved in browser storage.
Fit shows the whole image; 100% shows original detail. Select the Pan tool to drag the view. On a desktop, you can also hold Space or use right-drag. The image context menu is disabled inside the viewer.
The diff ratio is not a quality score. It counts pixels where any RGBA channel differs by more than the threshold. Compression, antialiasing, or a one-pixel shift can increase it. Colors are compared as decoded by the browser.
Share only the tool name and public URL. Your input and results are not included.
Visual comparison uses the original images. Pixel diff runs at full or reduced resolution according to a memory estimate, and the result identifies the mode. The changed ratio counts pixels where any RGBA channel exceeds the threshold; it is not a quality score. Images of different dimensions support visual comparison only.
Tested for creative and professional checks with high-resolution images. Processing stays in your browser and leaves the original files unchanged.
Images must be within 80 MP and a 12,000 px long edge, with up to 200 MB per file and 400 MB per pair. Even within these limits, supported sizes and processing time depend on your computer, browser, and available memory.
Inspect edits, export differences and alignment using side-by-side, overlay and pixel-diff views. Samples use original shapes drawn locally in your browser.
Samples replace the selected images A and B and comparison settings, then run the comparison. Images are generated locally and are not uploaded.
After trying multiple examples, repeat Restore previous input to return to your original input. History is kept only in this page; restore any input you need before closing it.
Image comparison restores the selected files and settings. The previous comparison result and full-screen state are not saved; compare again as needed.
Two 256×160 px PNGs: B changes the blue square in A to red, keeping its position.
Both images are 256×160 px. At threshold 0, the diff ratio is greater than 0%, concentrated in the recolored square.
B shifts the same original drawing 4 px to the right within an equally sized PNG.
The diff ratio is greater than 0%; overlay shows doubled edges. Alignment changes create differences even when the drawing itself is unchanged.
A is a PNG of the original drawing; B is the same canvas exported as JPEG at quality 0.35.
Both are 256×160 px. At threshold 0, the diff ratio is greater than 0%. Differences around edges can come from compression; exact values depend on the browser’s JPEG encoder.
Diff ratio is changed pixels divided by compared pixels, using the selected threshold. It does not score meaning or edit quality. Check alignment and dimensions, inspect the overlay, then calculate a pixel diff.
There is no automatic alignment. Threshold, compression, color or alpha differences, and reduced-preview processing affect the result. This does not determine image ownership, authorship or authenticity.
A channel difference equal to the threshold is excluded. In a 2×2 px image where one pixel’s red value changes from 0 to 11, threshold 10 gives 25% and threshold 11 gives 0%. Checked with the existing pixel-diff routine and original PNG/JPEG drawings. Read the result’s capability notice for limits and reduced-resolution processing.
No. Results are saved as new files; the originals are unchanged.
Processing takes place in your browser. Closing the page discards your work.
Different image dimensions support visual comparison only. Use equally sized images for pixel diff.
Keep any content you need before clearing. This tool does not autosave inputs or results. Reloading or closing the page, clearing inputs or resetting may discard your work.
Favorites and language preferences are stored separately and may be lost when site data is cleared. Tool resets and site-data deletion do not delete files already downloaded to your device.