About this tool
Resize to File Size uses a binary search algorithm to find the ideal quality and scale combination that gets your image under a specified file size — in KB or MB. Ideal for platforms with strict upload limits.
How it works
- 1Upload your image and enter a target file size in KB or MB.
- 2Choose your output format: JPEG, WebP or PNG.
- 3Click Optimise — the tool runs a binary search across quality and scale.
- 4The resulting file size, dimensions and quality level are shown before download.
Common use cases
- ✓Meeting email attachment size limits
- ✓Platform upload restrictions (estate agents, job boards)
- ✓Optimising images for slow connections
- ✓Reducing storage costs
Privacy first. Resize to File Size runs entirely inside your browser using the HTML5 Canvas API. Your images are never uploaded to any server, stored anywhere or shared with third parties. Everything happens locally on your device.
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