Convert BMP to JPG
BMP (bitmap) files are uncompressed and can be 10–50× larger than the same image as JPG. Converting to JPG makes them shareable by email, attachable to forms, and quick to load on the web.
To convert BMP to JPG, drop your bitmap above and choose a quality. Bitmaps store every pixel uncompressed, so a 25 megapixel BMP can be 75 MB on disk; the JPG equivalent at quality 90 is usually 2–5 MB with no visible difference. The tool decodes the BMP in-browser and re-encodes it with standard JPEG compression, then hands you a file you can email, attach or upload anywhere. BMP survives mainly in Windows utilities, older scanners, medical and industrial capture software, and retro game assets, which is why the files turn up unexpectedly large. The size reduction is the point: a 30 to 1 ratio is typical at quality 90. Two caveats. BMP can carry an alpha channel in its 32-bit form and JPEG cannot, so any transparency is flattened onto white. And JPEG's compression is tuned for photographic content, so pixel art and screenshots pick up visible ringing around hard edges and belong in PNG instead.
Drop a BMP here, or click to upload
Output: JPG
What happens when you convert BMP to JPG?
BMP (Windows Bitmap) is uncompressed by design — it was made in 1986 for Microsoft Paint, and its file layout stores raw RGB values with a small header. That makes it fast to open on old Windows machines but wildly wasteful on modern storage. Common sources today are: scanners saving at 300 DPI, industrial cameras, medical imaging workflows and older CAD tools. JPG is the standard compressed photo format (ISO/IEC 10918) and every OS, browser, printer and mobile viewer opens it without setup. Converting also strips the BMP's 54-byte header and any padding bytes that inflate the source further.
Common mistakes and limitations when going from BMP to JPG
JPG is lossy, so once you save you cannot recover the original pixel values. Keep the BMP master if the image is scientific, evidentiary or destined for further processing. JPG also has no transparency; BMP variants with alpha (rare) will be flattened onto white. Scanned line-art and diagrams sometimes compress poorly in JPG — for pure black-on-white document scans, PNG or PDF is a better target.
Choosing the right settings for BMP to JPG
BMP is uncompressed, so the source is enormous — a 1920×1080 24-bit BMP is about 6 MB regardless of content. Converting to JPG at quality 85 typically produces a file under 300 KB, a reduction of more than 95 percent, which is why this conversion is almost always worth making. Because BMP is lossless and uncompressed, this is a first-generation encode: no artefacts exist in the source, so the JPG will look as good as the quality setting allows. That is the ideal case for JPG and a reason to be slightly more generous than usual — quality 88 to 92 costs little relative to the saving already achieved. What to check is content type. BMPs commonly come from screenshots, scientific instruments, older Windows software and scanning hardware, and much of that content is interface graphics or line art rather than photographs. For those, JPG is the wrong destination and PNG will be both smaller and cleaner. BMP files can also carry an alpha channel in the 32-bit variant, though support is inconsistent. Where present, it is flattened onto white during this conversion. If the BMP came out of a design tool with transparency intact, convert to PNG instead. Because BMP carries no compression, the source file size tells you nothing about image complexity — a plain white 1920×1080 BMP and a highly detailed photograph at the same dimensions are both about 6 MB. That means you cannot judge from the file size whether JPG or PNG is the better destination; you have to look at the image. A useful test is to convert once to each format and compare. If the PNG comes out smaller than the JPG, the content is flat-toned graphics and PNG is correct. If the JPG is dramatically smaller, the content is photographic and JPG is correct. The comparison takes seconds and removes the guesswork entirely.
BMP to JPG conversion FAQ
Why is BMP so large?
- BMP stores every pixel as raw RGB with no compression. A 25-megapixel image occupies 75 MB as BMP but only 2–5 MB as a quality-90 JPG.
Will I notice quality loss?
- At quality 90 the JPG is visually indistinguishable from the BMP for photos, scans and screenshots.
Does the BMP get deleted?
- No. Conversion runs entirely in your browser and produces a new JPG blob; your BMP file stays where it is.
Can I convert 32-bit BMPs with alpha?
- Yes. The rare BMPv5 alpha channel is flattened onto white since JPG doesn't support transparency.
Should I use PNG instead for scans?
- For pure black-and-white line art or documents, PNG is often the better choice — JPG can introduce compression halos around sharp text.
What quality should I pick for scanned photos?
- 92 for archival, 85–88 for sharing. Both look identical on screen; 92 protects against generational loss if you re-save.
Does resolution stay the same?
- Yes. Pixel dimensions are preserved exactly; only the on-disk encoding changes.
Is BMP the same as TIFF?
- No. Both are common lossless formats, but TIFF supports layers, LZW compression and richer metadata; BMP is a simple flat bitmap.
BMP vs JPG at a glance
| Property | BMP source | JPG output |
|---|---|---|
| Compression | None | Lossy DCT |
| Typical size (12 MP image) | 35–75 MB | 1–3 MB |
| Transparency | Rare (BMPv5) | None |
| Best used for | Legacy Windows tools | Sharing, email, uploads |
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References: Microsoft BMP File Format specification, ISO/IEC 10918 (JPEG), Wikipedia comparison of raster image formats.