Convert BMP to JPEG
Drop a BMP file below and get a JPEG back. The conversion happens on your own machine, so nothing is uploaded and there is no size or quantity limit beyond what your browser can hold in memory.
Drop images here
Ctrl/⌘ VPaste a screenshot or copied image
Accepts BMP
Lower means a smaller file. 75 is a good default for photos.
100% in your browser Files are never uploaded.
Why convert BMP to JPEG?
Plenty of websites, content management systems and older desktop programs reject BMP uploads outright. JPEG is accepted just about everywhere, and that alone accounts for most of these conversions.
For the same picture, JPEG usually lands well under the size of the BMP original. That matters when you are trimming page weight or squeezing under an upload limit.
BMP files usually arrive from somewhere old: a scanner, Windows Paint, an industrial camera, a piece of line-of-business software written a long time ago. The format stores pixels essentially raw, which is why a single image can run to tens of megabytes. Converting to JPEG is one of the few conversions where the size difference is dramatic enough to be worth doing on its own.
Before you convert
Expect the file to shrink by 90 percent or more
An uncompressed 24-bit BMP spends three bytes on every single pixel regardless of content. A photograph that occupies 25 MB as BMP typically lands under 1 MB as a good-quality JPEG, with no difference your eye can find. This is the largest routine saving available in image conversion, and it is why almost nothing uses BMP for storage or transfer any more.
A big BMP does not mean a high-quality image
Size and quality are unrelated here. BMP faithfully stores whatever it was given — if the picture was screengrabbed from a compressed source, or exported out of a JPEG at some earlier point, all the existing damage is stored at full size along with everything else. Converting it to JPEG does not make it worse in any way you will notice; it just stops paying 25 MB to store a picture that was never that good.
Screenshots and diagrams are the exception
If the BMP holds flat colour, text or technical drawing rather than a photograph, JPEG is the wrong destination — it will put faint halos along every hard edge. PNG or WebP will look cleaner and, on that kind of content, usually come out smaller than the JPEG would anyway.
What carries over
- Pixel dimensions
- The photograph, visually intact
What does not
- Over 90 percent of the file size
- Transparency, in the rare BMP that has it
- Crisp edges on text and line art
BMP vs JPEG at a glance
| Property | BMP | JPEG |
|---|---|---|
| Compression | Lossless | Lossy |
| Transparency | No | No |
| Typical file size | 800-1200% of an equivalent JPEG | 100% of an equivalent JPEG |
| Compatibility | Supported by all current browsers and most apps | Opens everywhere, including decades-old software |
| Usually comes from | Older Windows software and scanners | Digital cameras and photo sharing |
Frequently asked questions
Are my BMP files uploaded anywhere?
No. The decoder and encoder are WebAssembly modules that run inside this page. The network tab may show a codec downloading the first time you use a format, but no request contains your file. On supported browsers, a codec that has already been used is cached so the same conversion can work offline.
Is there a file size or quantity limit?
There is no limit imposed by us. The practical ceiling is your device’s memory, since the image has to be held uncompressed while converting. On a typical laptop, images up to around 100 megapixels convert without trouble.
Will converting to JPEG lose quality?
JPEG is a lossy format, so some data is discarded. At the default quality setting the difference is not visible at normal viewing sizes. If you need an exact copy of the pixels, choose PNG instead.
Does it work on a phone?
Yes. The same WebAssembly modules run on mobile browsers. Conversion is slower than on a desktop because phone CPUs are weaker, and very large images are more likely to hit memory limits.
Why is my BMP file so large?
BMP stores pixels essentially uncompressed, so a single photograph can run to tens of megabytes. That alone usually makes the conversion worthwhile — expect the JPEG file to be a small fraction of the original with no visible difference.
What quality setting should I use?
For photographs, 75 to 85 is the range where most people cannot tell the result from the original at normal viewing size. Below about 60 you start seeing blocky artefacts around sharp edges. Above 90 the file grows quickly in exchange for very little visible gain.