Convert BMP to JPG

Turn heavy uncompressed BMP bitmaps into small, universally supported JPG photos.

BMP bitmaps store pixels with no compression at all, so even an ordinary photo can run to tens of megabytes. Converting BMP to JPG in your browser typically removes 90% or more of that size while keeping the picture usable everywhere.

Processed in your browser

Drop your image here

or choose an image from your device

Choose an image

Accepts BMP images · No fixed size limit — we adapt to what your device can handle. Very large files may take longer or show a warning.

About BMP to JPG

What a BMP file is

BMP (Windows Bitmap) is a raw raster format: the file is essentially width × height × 3 or 4 bytes of pixel data plus a small header. It dates from early Windows and is still produced by scanners, screen-capture utilities and some instrumentation software. Nothing about it is compressed, which is why the files are so large.

BMP vs JPG

JPG applies lossy compression designed for photographic content, discarding detail the eye is least likely to notice. For a photograph the visual difference at quality 85 is very hard to see, while the file becomes a small fraction of the BMP. For screenshots, diagrams and flat-colour bitmaps, JPG is a poor fit — sharp edges pick up coloured fringing, so convert those to PNG instead.

Transparency and BMP variants

32-bit BMPs can carry an alpha channel, but JPG cannot store transparency, so transparent areas are composited onto the background colour before encoding. Conversion relies on your browser's native BMP decoder, which covers standard 24-bit and 32-bit Windows bitmaps; very old RLE-compressed or OS/2 variants may fail to load, and the tool says so instead of producing a broken file.

Settings and output

The quality slider

Controls JPEG quantisation strength on the re-encode. 85 is a safe default for photographic bitmaps; push to 90+ for scans you'll print, or down to 75 if the only goal is a small email attachment.

When to use it

Making scanner or capture-software output small enough to email or upload.
Archiving a folder of bitmaps without filling a drive.
Preparing BMP photos for a website or form that rejects bitmap files.

Limitations to know

JPG compression is permanent; keep the BMP if you still need an exact master.
Screenshots and line art look better converted to PNG than to JPG.
Unusual or legacy BMP encodings may not decode in the browser.

Common problems and fixes

My BMP file won't load at all.

Old RLE-compressed or OS/2-format bitmaps aren't decoded by the browser's native BMP support. Re-save the file as a standard 24-bit or 32-bit Windows BMP first, or use whatever produced it to export PNG instead.

The JPG has coloured fringing around sharp lines.

That's normal JPEG behaviour on flat-colour or line-art content, not a bug. Convert that particular file to PNG instead of JPG.

Transparent areas in my BMP turned solid.

JPG can't store an alpha channel, so any transparency in a 32-bit BMP is filled with the background colour you chose before encoding.

How to use it

1Drop a BMP bitmap into the upload area.
2Note the original size — BMP stores pixels uncompressed, so even a modest photo can run to tens of megabytes.
3Set the quality slider (85 is a sensible default) and press Convert to re-encode the bitmap as JPG.
4Download the JPG and check the measured saving, which is typically 90% or more.

Frequently asked questions

Why are BMP files so large?

BMP writes every pixel as raw bytes with no compression at all — width × height × 3 or 4 bytes. JPG applies lossy compression tuned for photos, which is where the enormous saving comes from.

Will I see any quality loss?

At quality 85 and above the difference is hard to spot on photographic content. Screenshots and flat-colour bitmaps fare worse in JPG — convert those to PNG instead.

What about BMP files with transparency?

32-bit BMPs can carry an alpha channel, but JPG cannot. Transparent areas are composited onto the background colour you pick before encoding.

Which BMP variants are supported?

Whatever your browser can decode natively, which covers standard 24-bit and 32-bit Windows bitmaps. Very old RLE-compressed or OS/2 variants may fail to load, and the tool tells you rather than producing a broken file.

Is the BMP to JPG conversion free and does it add a watermark?

It is free with no signup and no watermark. The bitmap is decoded and re-encoded inside your browser tab, so there is no upload step and no per-file limit imposed by a server.