ICO in · ICO out
Compress ICO
Drop a ICO file, choose how hard to squeeze, and download a smaller ICO. The format never changes and the file never leaves your device.
Need a specific file size instead of a quality setting?
Get it under a size →Drop your image hereTap to choose images
Processed on your device. Nothing is uploaded.
ICO is lossless, so savings are limited. Convert to WEBP → usually goes much further.
Metadata stripped
EXIF and GPS are dropped during re-encoding.
Memory only
Files are released the moment you press Clear.
11 inputs accepted
PNG · JPG · JFIF · WEBP · AVIF · GIF · BMP · ICO · HEIC · HEIF · SVG
How ICO compression works
Icons are tiny already, so compression here is about picking the right pixel size rather than squeezing bytes. Under1MB re-wraps your icon around an optimised PNG at the size you choose, capped at 256 pixels — which is all any browser needs.
Need to hit an exact number?
Target sizes live on their own pages, where the quality search runs against your limit.
Three things worth knowing about ICO
Quality is fixed
ICO is lossless, so size only moves with dimensions or a change of format.
Compress from the original
Each lossy pass costs a little detail, so start from the master file rather than a file you already squeezed.
Nothing is uploaded
Your ICO is decoded and rewritten by the browser. Watch the network tab stay empty.
Questions
How small should a favicon be?+
A 256px ICO usually lands well under 50 KB and covers every browser.
Is transparency kept?+
Yes — the PNG inside the icon keeps its alpha channel.
Can it get my ICO under 1 MB?+
Comfortably. Most icons come out as a few tens of kilobytes.
Can I compress ICO files to an exact size?+
Yes — the size pages do that. Pick a limit like 500 KB and we search for the highest quality that fits underneath it.
Are my ICO files uploaded anywhere?+
No. Compression happens inside your browser, so the file never leaves your device and nothing is stored.
Is EXIF and GPS data removed?+
Yes. Re-encoding writes a clean file without camera, date or location metadata.
Your images. Your device. Your privacy.
Compress as many ICO files as you like — free, private, no account.
Try Under1MB free