BMP to JPG
Convert large BMP bitmap files to compressed JPG format
Drop BMP files here
Select one or more BMP images
Max file size: 100MB
100% Private: All processing happens in your browser. Your files never leave your device.
BMP is the bitmap format Windows has used since the early 1990s: it stores every pixel's color value directly, with little to no compression, which is why old scanners, MS Paint, and some screen-capture and point-of-sale software still default to it. Windows Photos and most Windows apps open a BMP without complaint, but many web forms, chat apps, and email clients either reject it outright or handle it clumsily. This tool decodes your BMP and re-encodes it as JPG entirely in your browser, using canvas, so it opens and uploads everywhere else without you needing separate desktop software.
Because it's converting to JPG specifically, the result is always a lossy, compressed file with no transparency channel — if your BMP happens to be a 32-bit file with an alpha channel, that transparency is discarded and replaced with solid white, since JPG has no way to represent it. The quality slider controls exactly how much detail that lossy step keeps, and files up to 100 MB are accepted, a much higher ceiling than most tools on this site, reflecting how large an uncompressed bitmap can get.
How it works
1. Drop or browse your BMPs
Drag one or more .bmp files onto the upload area, or click it to browse. Each file can be up to 100 MB.
2. Set JPG quality
Move the JPG Quality slider between 10% and 100% in steps of 5 — it defaults to 85%.
3. Convert to JPG
Press "Convert N BMPs to JPG." Each bitmap is decoded, flattened onto a white background, and compressed in turn.
4. Download your JPGs
Download a single result directly, or press "Download All" to get every converted file zipped together.
When you'd use it
A scan or fax saved as BMP
Older scanners, fax software, and some multi-function printers still default to saving BMP. Converting to JPG shrinks it enough to actually attach to an email or upload to a portal.
A huge Windows screenshot or Paint file
A full-screen BMP screenshot can run into tens of megabytes for a single image. Compressing it to JPG makes it practical to share or store.
Legacy business software exports
Some point-of-sale terminals, industrial scanners, and older line-of-business systems still export images as BMP by default, long after the rest of a workflow has moved to JPG or PNG.
Sending several BMP scans over chat or email
Messaging apps and mail providers frequently strip or block BMP attachments, or balk at their size. Batch-converting a folder of scans to JPG first avoids that friction.
Why BMP files are so large to begin with
A BMP stores the color of every single pixel with essentially no compression, unlike JPG or PNG, which both apply real compression algorithms before saving. That's the direct reason a BMP of a given photo is routinely five to ten times the size of the same picture as a JPG, and it's also why this tool's upload limit is set to 100 MB per file rather than the smaller ceilings used elsewhere on the site — a moderately sized BMP can genuinely be that big.
Choosing a JPG quality
The slider defaults to 85%, a middle-ground setting that keeps most visible detail while still compressing heavily compared to the uncompressed BMP. Dropping it toward 10% shrinks the file further but introduces visible blockiness, especially around sharp edges and text; pushing it toward 100% keeps the image closer to the original at the cost of a larger download. For scanned documents and diagrams with fine lines, staying above 70% generally avoids noticeable artifacts.
What happens to transparency
Most BMPs don't carry transparency at all, but the less common 32-bit variant can include an alpha channel. Before encoding, this tool always fills the canvas with solid white and then draws your bitmap on top, which means any transparent pixels a source BMP might have are replaced with white in the finished JPG — JPG itself has no mechanism to store transparency, so there's no setting that changes this. If keeping transparency matters for your image, converting to PNG instead preserves it.
Frequently asked questions
Will my BMP's transparency survive conversion to JPG?
No. JPG doesn't support transparency, so this tool fills the canvas white before drawing your bitmap on top; any transparent pixels in a 32-bit BMP become solid white. Convert to PNG instead if you need to keep an alpha channel.
What JPG quality should I use?
85%, the default, is a reasonable middle ground. Go lower for smaller files if some blockiness is acceptable, or push toward 100% for scans and documents with fine detail where compression artifacts would be distracting.
How large a BMP file does this accept?
Up to 100 MB per file — a higher ceiling than most converters here, since BMPs store pixels uncompressed and can genuinely reach that size.
Can I convert a whole folder of BMPs at once?
Yes. Drop as many files as you like; they're processed one after another and can be downloaded individually or together as a ZIP.
Why is my JPG so much smaller than the BMP I uploaded?
BMP stores every pixel with no compression at all, while JPG applies lossy compression tuned by the quality slider. Going from uncompressed to compressed is what produces the large size drop, not anything specific to this tool.
What happens if I drop a file that isn't a BMP?
It's silently left out of your file list with no error shown, so double-check the file extension if something you dropped doesn't appear.