MRW to BMP3 Converter
FileFlip converts MRW to BMP3 entirely inside your browser, using ImageMagick compiled to WebAssembly. The file is never uploaded to a server: it is read off your disk, converted on your own machine, and saved back by the browser. That means no file-size limit, no queue and no account.
How do I convert an MRW file to BMP3?#
- Drop your MRW file onto the converter at the top of this page, or click it to pick one from your computer. You can add as many as you like.
- Leave the target set to BMP3 and the conversion starts on its own. FileFlip downloads 14.1 MB of WebAssembly the first time and nothing after that, then runs ImageMagick on your own machine.
- Save the BMP3 file. Your browser writes it straight to your downloads folder, because there was never a server holding it.
Does converting MRW to BMP3 lose quality?#
No. Converting MRW to BMP3 writes the data out again without discarding any of it, so nothing that was in the MRW file is lost on the way. What changes is the size of the file, not what is inside it.
Is it safe to convert MRW files online?#
Yes, because nothing is uploaded. FileFlip converts MRW files inside the browser tab you already have open, using WebAssembly builds of the same engines a desktop converter would install. Your file is read from your own disk into the page's memory, and no request carrying it is ever made.
You do not have to take that on trust. Open your browser's network panel, run a conversion, and you will see the engine come down and your file go nowhere. There is no upload, no server-side copy, no retention window, and no account tied to what you converted.
How FileFlip works lists every engine, its version and its download size, and shows how to check for yourself that nothing leaves your machine.
What MRW to BMP3 actually does to the file#
Converting MRW to BMP3 runs on ImageMagick, downloads 14.1 MB of WebAssembly the first time and nothing after that, writes the data out again without discarding any of it.
| Engine | ImageMagick |
|---|---|
| Conversion path | One step: MRW → BMP3 |
| Downloaded to your browser | 14.1 MB, once, then cached by your browser |
| Quality | Lossless |
| You get back | One file |
| Where it runs | In a background worker, so the page stays responsive |
Worth knowing before you start:
- camera raw is demosaiced with ImageMagick's defaults, which will not match the camera's own rendering
- some cameras write lossily compressed raw, so the source is not always a complete sensor record
What is an MRW file?#
An MRW file stores the unprocessed sensor data captured by a Minolta DiMAGE or Dynax/Maxxum digital camera, the raw format Minolta used until Sony bought its camera division in 2006 and switched the successor Alpha line to ARW.
Keep a file as MRW only if it is an original capture from a Minolta DiMAGE or Dynax/Maxxum camera you want to preserve unchanged.
Convert MRW to DNG or TIFF for long-term storage or editing, since no current camera writes the format and support for it is unlikely to improve.
What is a BMP3 file?#
BMP3 is ImageMagick's name for a Windows bitmap saved with the 40-byte BITMAPINFOHEADER that Windows 3.0 introduced in 1990, an encoding choice rather than a different file format, and it's the header structure the overwhelming majority of ordinary .bmp files already use.
Choose BMP3 for maximum compatibility, since it's the header format nearly all BMP-reading software expects.
Convert away from BMP to PNG when the image needs transparency, or when you want lossless compression smaller than BMP3's largely uncompressed pixel data.
MRW to BMP3 questions people ask#
What camera shot this MRW file?
MRW files come from Minolta digital cameras, starting with the DiMAGE 7 in 2001 and continuing through later DiMAGE models and the Dynax/Maxxum 5D and 7D DSLRs. Sony's first Alpha DSLR, released in 2006 after it acquired Konica Minolta's camera business, switched to the ARW format instead.
Can I still open an old MRW file?
Yes. MRW files open in RawTherapee, darktable and digiKam, all of which use the dcraw/LibRaw decoding libraries that support the format, and ExifTool reads and writes their metadata. No Minolta software has been updated in years, so a modern raw processor is the more reliable option.
Should I convert MRW files to something else?
Converting MRW to DNG or TIFF is worth doing for long-term storage, since Minolta stopped making cameras in 2006 and fewer applications add new support for a format tied to a discontinued camera line every year.
What is BMP3?
BMP3 is ImageMagick's name for a standard Windows bitmap written with the 40-byte BITMAPINFOHEADER, not a separate format. It's the same header structure that almost every ordinary .bmp file already uses.