BMP
Simple, typically uncompressed raster format producing large, exact pixel files.
Conversion tools
Compression tools
Format details
What is BMP?
BMP (Bitmap) is a straightforward raster format that stores pixel data with little or no compression. Files are large but simple to read and write, which makes BMP common in legacy Windows software, embedded systems, and workflows that want an exact pixel copy without codec complexity. It is rarely used on the modern web.
Specifications
- Typical file size
- Screen-sized images: 1-10 MB. Full-resolution photos: 10-50 MB or more, since size scales with width x height x bit depth.
- Quality
- Pixel-exact because typical BMP variants apply no compression, though this comes at the cost of very large files.
- Transparency support
- No — Common 24-bit BMP has no alpha; 32-bit BMP can carry an alpha channel but support is inconsistent.
- Animation support
- No — BMP is a single-frame format.
- Compression type
- Usually uncompressed; optional simple RLE variants exist but are uncommon
- Browser support
- Supported in most browsers but rarely used on the web.
- Compatibility
- Native on Windows and widely supported by desktop editors. Some phone and web tools may need a conversion step.
Advantages
- Simple format that is easy for legacy tools to read
- No lossy compression, so pixels are exact
- Reliable for embedded and industrial workflows
- Straightforward to script and generate
Disadvantages
- Very large files compared to PNG or JPG
- No standard support for smooth transparency in common variants
- Inefficient for web or email use
- Rare in modern design pipelines
Common uses
- Legacy Windows applications
- Embedded devices and simple firmware displays
- Exact-pixel intermediate exports
- Testing and QA of image pipelines
- Icons and cursors in older software
Common conversions
- BMP to JPG
- BMP to PNG
- BMP to WebP
Compression tips
- BMP itself has almost no compression, so convert to PNG for lossless size savings
- Convert to JPG or WebP for photographic content going to the web
- Resize before exporting because BMP size scales directly with resolution
- Reduce bit depth if the target workflow accepts it
- Keep BMP only when a downstream tool specifically requires it
Frequently asked questions
Standard BMP stores raw pixel data without compression, so file size grows directly with resolution and bit depth.
No. Use PNG for lossless graphics and JPG, WebP, or AVIF for photos. BMP wastes bandwidth without any quality gain.
Common 24-bit BMP does not. A 32-bit BMP can carry alpha, but many viewers ignore it, so PNG or WebP is safer.
Yes. PNG is lossless and typically much smaller than BMP for the same pixel data.