How to convert BMP files to PNG
Convert one BMP image or a batch of up to 50 into PNG in your browser, then check image quality, transparency, and file size before sharing.
You have a BMP image that a website, app, or person will not accept, and you need a PNG copy. Converting the file changes its format, but it does not redraw the image or automatically remove its background.
Use TooLab's Image Converter to convert BMP images to PNG in your browser. You can convert up to 50 images at once, then check that the new files look right before you send or upload them.
Convert BMP files to PNG
- Open the Image Converter.
- Choose or drag your BMP file into the converter. To convert several images together, add up to 50 files.
- Choose PNG as the output format.
- Start the conversion and save the resulting PNG file or files to your device.
- Open a converted image and check the full picture, especially its edges, colors, and any areas that should be transparent.
Keep the original BMP until you have checked the PNG and confirmed that the website or app accepts it. The converted file may have a different name or extension, so look for .png at the end of the saved filename.
What to expect from the PNG
The picture looks the same
That is usually the result you want. PNG uses lossless compression, which means it can reduce file size without throwing away image details. BMP images are often uncompressed or stored with less efficient compression, so a PNG may be smaller, particularly for screenshots, diagrams, icons, and images with large areas of one color.
The PNG is larger than the BMP
This can happen, especially with photographs or images that contain lots of fine detail and color variation. PNG is designed to preserve exact image data, not to make every image as small as possible. If a site has a strict file-size limit, check that limit before converting. Do not assume that changing the format will always shrink the file.
The image still has a solid background
PNG can store transparent pixels, but converting an ordinary BMP does not make its background transparent. The converter can only preserve transparency if it exists in the source image and is supported by the source file. To remove a background, use an image editor to select and erase it, then save the result as PNG.
The PNG does not open or looks different
Check the saved filename and make sure it ends in .png. Then try opening the original BMP and the converted PNG in the same image viewer. If the original also looks wrong, the issue may be in that file rather than the conversion. Color profiles and the viewer can affect how colors appear on screen, so a small visual difference does not always mean image data was lost.
How to fix conversion problems
- Check that the file is a BMP. Look at the filename ending, such as
.bmp, and make sure you selected the image you intended. A renamed file is not necessarily a BMP, even if its name ends with.bmp. - Try one image by itself. If a batch does not finish, convert a single BMP first. Large images or a large group of files can use a lot of browser memory. If one works, add the rest in smaller groups.
- Check the saved file's extension. Make sure the output is a PNG file ending in
.png, not a BMP that was only renamed. Open it in an image viewer to confirm it loads. - Reload the converter and try again. If the conversion stops or the page becomes unresponsive, reload the page and add the file again. Close other demanding browser tabs first if your computer is low on available memory.
- Test a fresh copy of the source. If the BMP will not open or convert, make a copy from the original source, such as the device or application that created it, and try that copy. A damaged or incomplete BMP may need to be recreated before it can be converted.
When to use PNG instead of another format
PNG is a good choice for screenshots, logos, diagrams, text, icons, and artwork with sharp edges. It preserves fine lines and can support transparency, which is useful when an image needs to sit over a colored background. It is also widely accepted by websites and editing apps.
For a photo, PNG may create a much larger file than a format designed for photographs. If a service accepts another format and file size matters, check its requirements before choosing PNG. For transparent artwork, PNG is often more suitable than JPEG because JPEG does not support transparency.
The Image Converter processes your files in the browser, and the images you open stay on your device.
