Turn JPG files into BMP
This makes a BMP out of the JPG you already have. BMP is the usual choice for windows application resources and legacy tooling. Expect the BMP to be a good deal bigger, which is what keeping every detail costs. Your file never leaves your computer.
Need the other direction? Convert BMP to JPG
How to convert JPG to BMP
- 1 Drop your JPG .jpg or .jpeg or .jpe file onto the page, or click to browse for it.
- 2 Check the options. Nothing is thrown away on the way to BMP, so there is no quality dial to set.
- 3 Convert. The work happens on your own machine, so how long it takes depends on your computer and the file.
- 4 Download the BMP, or add more files and do the whole set in one go.
Why convert JPG to BMP
- You want a copy that will not get any worse each time you edit and save it, and BMP gives you that.
- Nothing is squeezed, so there is nothing to go wrong and nothing to unpack.
- Simple enough that almost any program can read it.
- Embedded devices and firmware that cannot afford a decoder.
- JPG: no transparency: see-through areas come out on a solid colour.
JPG compared with BMP
How the two formats differ on the things that decide whether a conversion is worth making.
| Property | JPG | BMP |
|---|---|---|
| File extension | .jpg | .bmp |
| Compression | Lossy | Uncompressed |
| Transparency | No | Yes |
| Colour depth | 8 bits per channel, 24-bit colour | 1, 4, 8, 16, 24 or 32 bits per pixel |
| Typical file size | Smaller | Largest |
| Browser support | Every browser | All current browsers |
| Introduced | 1992 | 1986 |
| Developed by | Joint Photographic Experts Group | Microsoft |
| Standard | Open | Proprietary |
Quality and what changes
BMP stores every pixel exactly, but it can only preserve what the JPG already contained. The compression artefacts baked into the source are preserved perfectly along with everything else, so the picture does not improve, it just stops degrading. Expect the file to grow substantially, often several times over, because JPG was discarding data that BMP now has to write out in full.
- One BMP limitation to keep in mind: files are enormous, often ten to fifty times a comparable PNG.
Questions about JPG to BMP
Does converting to BMP add transparency?
It makes transparency possible but it cannot invent it. There is nothing see-through in a JPG to recover, so the background stays exactly as solid as it was. Removing a background is a separate editing step.
Does converting JPG to BMP improve the quality?
No. BMP preserves what it is given perfectly, including the compression artefacts already present in the JPG. It stops further loss from happening, which is worth doing before editing, but it cannot recover detail that was discarded.
Why is my BMP bigger than the JPG?
Because JPG was discarding data and BMP is not. A lossless format has to write out every pixel it is handed, artefacts included, so growing several times over is normal and does not mean anything went wrong.
Is my JPG file uploaded anywhere?
No. The whole thing runs inside the browser tab you already have open. Your JPG is read straight from your own disk, converted on your machine and handed back as a BMP. Nothing is sent anywhere, nothing is stored and there is no account.
Is there a file size limit?
There is no server-side limit because no server sees the file. The real ceiling is your device memory, since the input and the output both have to fit in the tab. A few hundred megabytes is usually fine on a desktop machine and considerably less on a phone.
Can I convert several JPG files at once?
Yes. Add as many as you like and they are processed one after another, then offered as separate BMP downloads or as a single ZIP. Speed depends on your own processor rather than on a queue.
Does the converter work offline?
Yes, after the page has loaded once. The engine is cached by the browser, so you can disconnect, reload and keep converting. That falls out of doing the work locally rather than being a separate mode you switch on.