BMP to WebP Converter

What happens when you convert BMP to WebP

• The image is decoded and written as a lossy WebP at 90 percent quality, keeping transparency.
• BMP is lossless and WebP is not, so the file shrinks a lot, at the cost of some fine detail around sharp edges.

How to convert BMP to WebP online

1. Press "Choose BMP files" and select one or more files, or drag them onto the box. You can add files of any size your device can hold in memory.
2. Adjust the settings if you need to. Lower quality gives a smaller file.
3. Press "Convert to WebP". Images convert in a second or two each.
4. Save each WebP with its download button. Close the tab and every trace of the files is gone from memory.

Why convert BMP to WebP?

BMP files usually come from Windows software, embedded displays and legacy tools. People convert them to WebP because WebP makes images much smaller for websites while keeping transparency.

In short, BMP is good at what it was made for, and WebP is the more practical choice when the file has to open, upload or print somewhere else. BMP opens in browsers and every Windows image tool, while WebP opens in all current browsers; older Photoshop and Windows Photo versions cannot open it.

How to convert BMP to WebP on Windows, Mac, iPhone and Android

On Windows

Open this page in Chrome, Edge or Firefox, drag your BMP files in from File Explorer, and press Convert. Each WebP is saved to your Downloads folder.

On a Mac

Safari, Chrome and Firefox all work. Drag the BMP files from Finder onto the drop zone and the WebP files land in Downloads.

On iPhone and iPad

Open the page in Safari and tap Choose BMP files. You can pick from Photos or from the Files app. The converted WebP appears in Files, in the Downloads folder; to put it in your photo library, open it there, tap Share and choose Save Image.

On Android

Open the page in Chrome, tap Choose BMP files and pick them from Files or your gallery. The WebP is saved to the Download folder, where any file manager can find it.

Best settings for BMP to WebP

WebP is lossy, so the Quality setting trades file size against detail. Best is 95, High is 90, Medium is 80 and Small file is 65 on the usual 0 to 100 scale. At High the difference from the BMP is invisible for photos; at Small file you may see softness around text and fine patterns.

The Maximum width setting shrinks large images before encoding. A 4000 pixel phone photo reduced to 1920 pixels loses three quarters of its pixels and most of its size, yet still fills a laptop screen.

BMP vs WebP: the differences

About BMP and WebP files

What is a BMP file?

BMP usually stores pixels with no compression at all, so a 12 megapixel photo is about 36 MB. That size is the price of being readable by almost any program ever written for Windows.

What is a WebP file?

WebP can be lossy or lossless and still keep transparency, and at the same visual quality it usually lands 25 to 35 percent smaller than JPG. It is the reason so many images saved from websites turn out not to be JPGs.

BMP to WebP not working? Common problems

• Colours look slightly different. Browsers convert images to the standard sRGB colour space when they decode them, so wide-gamut and CMYK images can shift a little.
• A phone photo comes out upright even though it looked sideways elsewhere. That is correct: the rotation stored in the photo is applied during conversion, so the WebP is always the right way up.
• The file is bigger than expected. The WebP is usually far smaller, because lossy compression discards detail the BMP kept.

Convert BMP to WebP from the command line

If you work in a terminal, ImageMagick converts BMP to WebP in one line:

magick input.bmp -quality 90 output.webp

To convert every BMP in a folder at once, use magick mogrify -format webp *.bmp. The converter on this page does the same job without installing anything.