BMP files come out of old scanners, Windows tools and some medical and industrial software, and they are enormous: an uncompressed bitmap can be twenty times the size of the same picture as a JPG. This page shrinks them without visible loss.
Set a maximum width or a kilobyte limit if a form needs one; otherwise the picture keeps its pixels and simply becomes a normal JPG that opens anywhere and attaches to any email.
The conversion happens on your device; the scans are never uploaded.
How to use it
Add one BMP file or a whole batch.
JPG is already selected as the output; set a maximum width if you also want it smaller.
Press Convert. Each image is decoded and re-encoded on your device.
Download one file, or a ZIP for a batch.
Supported formats and limits
Input
BMP (any bit depth your browser can decode)
Output
JPG, or PNG for screenshots
Batch
Yes
Where it runs
In your browser; nothing uploaded
Not for: Preserving a lossless master — keep the BMP if you will edit the picture again.
Frequently asked questions
Are my files uploaded to a server?
No. This conversion runs entirely inside your browser using your own device’s processing power. The file never leaves your computer or phone, which is why it also works when your connection drops.
Will the JPG look worse than the BMP?
At the default quality the difference is invisible for photographs and scans. Screenshots with fine text keep more detail as PNG — pick PNG for those.
How much smaller will it be?
Typically ten to twenty times smaller, because BMP stores every pixel uncompressed.