Compress Image to 50 KB
Meet a 50 KB limit — an email signature, a contact form, a marketplace thumbnail, a CMS with a hard cap — without ending up with an unreadable thumbnail. Furtu searches for the best quality that fits, shrinks the pixels only as far as it has to, and reports exactly what it did.
The finished file is guaranteed to be at or under this. 50 KB is a hard limit for a lot of forms, so this is the setting most people need.
The lowest quality Furtu will use. At a target this small the image usually has to lose pixels as well as quality, so this floor is what stops it going too far.
How compress image to 50 kb works
- Add your imagesDrop in the file that has to fit 50 KB. Up to 20 at once, each validated before it is decoded.
- Set the target and the floor50 KB is the default. The quality floor is the line Furtu will not cross, so a very aggressive limit cannot quietly destroy the picture.
- Download the fitted filesEach file comes back with its achieved size, the quality used, and the dimensions — including whether they had to be reduced.
What you get
Squeeze an image under 50 KB for the places that will not allow more. Everything happens inside this page: the file is read by your browser, transformed in memory and handed straight back to you as a download. There is no upload queue, no waiting for a server, and nothing left behind when you close the tab.
Supported formats
Furtu accepts .jpg, .jpeg, .png, .webp, .avif, .gif, .bmp, .svg, .ico, .heic, .heif files up to 100 MB each, and processes up to 20 files in one run.
- Every file is checked against its real file signature, not just its name, so a renamed or corrupt file is rejected with an explanation instead of failing halfway through.
- Files over the limit are refused up front rather than after a long wait.
Limitations, stated up front
- At this size the pixel dimensions usually have to be reduced, not just the quality. The note on every file states the original and the new size so the trade is visible.
- The target is a ceiling rather than an exact figure, though Furtu aims to land as close under it as possible.
- If the target is unreachable at your quality floor, or below 64 pixels on the long edge, Furtu reports the problem instead of returning a file that is too small to be usable.
- SVG and animated GIF are rejected. A canvas cannot re-encode vector art or preserve GIF animation, so both are refused with an explanation.
Frequently asked questions
Is 50 KB realistic for a photo?
For a full-resolution photograph, no — and pretending otherwise would be dishonest. 50 KB is roughly what a 640×480 image looks like at a decent quality. Furtu therefore does two things: it searches for the best quality that fits, and if that is not enough it reduces the pixel dimensions step by step, stopping as soon as the file fits. You get the largest image that honours the limit, not a squashed version of the original.
What happens if the image cannot get that small?
Furtu stops and tells you rather than producing something unusable. There are two points where it gives up: when it would have to go below your quality floor, or when the long edge would fall below 64 pixels, which is too small to be worth returning. Raise the target, lower the floor, or accept a smaller image on purpose.
Are the images uploaded?
No. The search for the right quality and size runs entirely in your browser on your own device. Nothing is transmitted, which is exactly what you want for the images people are forced to shrink — passport photos, ID documents, signatures, avatars.
Will it shrink the dimensions as well as the quality?
Yes, but only when it has to. Furtu first tries to reach the target at your original dimensions by lowering quality alone. If that fails it scales the image down and searches again, then walks the dimensions back up to fill the budget as fully as possible. The note on each file states whether the dimensions changed and gives the original size.
Which format does it produce?
WebP, wherever the browser supports it, because WebP needs noticeably fewer bytes than JPG for the same perceived quality and so keeps more of your 50 KB budget. If your browser will not encode WebP, Furtu falls back to JPG and names the file accordingly.