Convert BMP to JPEG XL
Drop a BMP file below and get a JPEG XL 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
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 XL?
For the same picture, JPEG XL usually lands well under the size of the BMP original. That matters when you are trimming page weight or squeezing under an upload limit.
JPEG XL supports an alpha channel, so you can cut out a background after converting. The conversion itself will not invent transparency that the BMP file never had.
BMP vs JPEG XL at a glance
| Property | BMP | JPEG XL |
|---|---|---|
| Compression | Lossless | Lossy |
| Transparency | No | Yes |
| Typical file size | 800-1200% of an equivalent JPEG | 45-60% of an equivalent JPEG |
| Compatibility | Supported by all current browsers and most apps | Safari and recent Chrome; still uncommon elsewhere |
| Usually comes from | Older Windows software and scanners | Long-term archives and photography workflows |
Frequently asked questions
Are my BMP files uploaded anywhere?
No. The decoder and encoder are WebAssembly modules that run inside this page. You can verify it by opening your browser’s network tab — converting a file produces no outbound requests. You could even disconnect from the internet after the page loads and it would still work.
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 XL lose quality?
JPEG XL 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 XL file to be a small fraction of the original with no visible difference.
Is JPEG XL ready to use?
Partly. Safari has supported it for some time and Chrome shipped stable support in early 2026, but overall coverage still sits around 15%. It is a sound choice for archiving, where compression quality matters more than universal support, and a poor one for images going onto a public website today.