An online image comparison tool. Upload two images and use a draggable divider to view them side by side and spot the differences. Adjust the split by dragging or with the keyboard, which makes it handy for design reviews and before/after checks.
Choose two images to compare them side by side here
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Drag the divider left or right; when focused you can also fine-tune it with the ← → keys (hold Shift for larger steps)
Tip: comparison is most accurate when both images share the same dimensions