Image Format Comparison

PNG vs BMP: Why PNG Wins for Almost Every Use Case

BMP was the default image format in early Windows — Microsoft Paint saved BMP by default, Windows wallpapers were BMP, and the format was everywhere in the 1990s and early 2000s. It's lossless, like PNG, but that's where the similarity ends. BMP stores image data as raw pixel values with no compression — resulting in enormous file sizes. A 1920×1080 screenshot is about 6 MB as BMP and about 500 KB as PNG. There is essentially no reason to use BMP today over PNG.

PNGvsBMP

Quick Verdict

Use PNG when…

Use PNG for virtually everything: web images, logos, icons, screenshots, transparent graphics. PNG is lossless like BMP but dramatically smaller.

Use BMP when…

Use BMP only when a legacy Windows application specifically requires BMP format and won't accept PNG. In all other cases, PNG is strictly better.

PNG vs BMP: Feature Comparison

Feature	PNG	BMP
Compression	Lossless DEFLATE compression	Usually uncompressed (some BMP variants have RLE compression)
File size	Small to moderate — typical screenshot 200 KB–1 MB	Very large — same screenshot might be 5–15 MB uncompressed
Transparency	Full alpha channel transparency	No transparency support in standard BMP
Bit depth	1, 2, 4, 8, 24, or 32-bit colour	1, 4, 8, 16, 24, or 32-bit colour
Web browser support	Universal	Technically supported but rarely used on web
Software support	Universal	Universal on Windows, less so elsewhere
Best for	Everything — web, design, screenshots, icons	Legacy Windows applications that require BMP

When PNG wins

✓Compression: Lossless DEFLATE compression
✓File size: Small to moderate — typical screenshot 200 KB–1 MB
✓Transparency: Full alpha channel transparency

When BMP wins

✓Compression: Usually uncompressed (some BMP variants have RLE compression)
✓File size: Very large — same screenshot might be 5–15 MB uncompressed
✓Transparency: No transparency support in standard BMP

Frequently asked questions

Is BMP still used anywhere?

BMP persists in a few niche areas: some Windows printer drivers accept only BMP, certain legacy manufacturing and industrial software requires BMP input, and some Windows application resource files (like custom cursors and icon source files) use BMP internally. For everyday photography, web graphics, or anything modern, BMP is obsolete.

Can I convert BMP to PNG without losing quality?

Yes — both BMP and PNG (standard 8-bit) are lossless. Converting BMP to PNG with FormatDrop produces a pixel-identical image that is typically 80–90% smaller. There is no quality trade-off, only a size reduction.

Why does Windows Paint still save BMP by default?

Historical compatibility — Paint has been in Windows since version 1.0 in 1985, and BMP has always been its native format. Modern Paint on Windows 10/11 can save PNG, JPG, and other formats, and PNG is generally the better choice for new work.