Converts PNG to BMP. You almost certainly want this only because something specific requires it — an embedded display, an industrial controller, an old Windows utility, a test fixture that reads raw pixels.
What is written
BITMAPINFOHEADER, uncompressed (BI_RGB), stored bottom-up with BGRA channel order. That is the most widely accepted BMP variant — every reader from Windows 3.1 onwards handles it, and it keeps the alpha channel.
Bottom-up row order looks like a mistake and is not: it is the original BMP convention and the one that ancient readers assume.
The file will be very large
Alpha is kept but often ignored
Why anyone still wants a BMP
Other names for this
Also searched as “png to bitmap”, “convert png to bmp”.
Questions
- Why is the file so enormous?
- BMP does not compress. Four bytes per pixel, always, whatever the image contains.
- Is transparency kept?
- It is written into the 32-bit format, but many BMP readers ignore alpha. Set a background colour if the target software renders it strangely.
- Can I convert a whole folder of images?
- Yes. Drop as many files as you like, or a whole folder. Each keeps its original name with the new extension —
IMG_4032.heicbecomesIMG_4032.jpg, neverconverted_1.jpg— and you can download them individually or as a ZIP. - Are my photos uploaded?
- No. The decoding and re-encoding happen in this tab using the browser’s own image support. Photos are personal in a way most files are not, and none of them is transmitted. Turn your Wi-Fi off and the converter keeps working.
- How large an image can I convert?
- The practical ceiling is the browser’s canvas limit, about 268 million pixels in total area — roughly 16,000 × 16,000. Above that you get a clear error rather than a silent failure, and resizing first is the fix. File size itself is limited only by your device’s memory.