Free webp to jpg
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Image MIME Reference
BMP

Windows Bitmap (Legacy Windows MIME Alias)

image/x-windows-bmp
VS

WebP Image

image/webp
WebP

A complete technical comparison of Windows Bitmap (Legacy Windows MIME Alias) and WebP Image — covering compression, feature support, browser compatibility, magic bytes, and when to choose each format.

Equal browser support

Feature Support

Feature BMP WebP
Transparency (Alpha) Yes Yes
Animation Support ✕ No Yes
Progressive Loading ✕ No ✕ No
HDR Support ✕ No ✕ No
EXIF Metadata ✕ No Yes
ICC Color Profile Yes Yes
Windows Bitmap (Legacy Windows MIME Alias)
image/x-windows-bmp
Extension
.bmp.dib
Container DIB (Device-Independent Bitmap)
Compression Uncompressed / Run-Length Encoding (RLE)
Algorithm
NoneRLE4RLE8
Color Depth 1-bit (Monochrome), 4-bit (16 colors), 8-bit (256 colors), 16-bit (High Color), 24-bit (True Color), 32-bit (True Color with Alpha)
Developed by Microsoft Corporation
Released 1985
Magic Bytes
42 4D
Full BMP reference →
WebP Image
image/webp
Extension
.webp
Container RIFF
Compression Lossy / Lossless
Algorithm
VP8VP8L
Color Depth 8-bit
Developed by Google
Released 2010
Magic Bytes
52 49 46 46 XX XX XX XX 57 45 42 50
Full WebP reference →

Browser Support Comparison

Browser BMP WebP
Chrome Chrome
✓ 1
✓ 32+
Firefox Firefox
✓ 1
✓ 65+
Safari Safari
✓ 1
✓ 14+
Edge Edge
✓ 12
✓ 18+
IE IE (Legacy)
✓
 ✕
BMP

BMP Strengths

  • Universally supported by all major operating systems and modern web browsers
  • Maintains perfect, lossless fidelity because pixel data is stored without lossy compression artifacts
Limitations
  • Massive file size overhead due to a lack of modern compression algorithms
  • Legacy MIME strings like 'image/x-windows-bmp' can trigger validation warnings in strict security or API environments if unhandled
WebP

WebP Strengths

  • Superior lossy compression — 25–35% smaller than JPEG at equivalent quality
  • Supports both animation and full alpha transparency
  • Lossless mode available with smaller file sizes than PNG
Limitations
  • Slower encoding than JPEG, especially for lossless
  • Not supported in Internet Explorer or very old browsers

When to choose which format

BMP
Use BMP when…
  • Legacy Windows Desktop Registry Associations
  • Older Enterprise Intranet Applications
  • Windows Graphics Archival
WebP
Use WebP when…
  • Websites
  • Ecommerce
  • Mobile Apps
  • CMS Images

More comparisons

BMP vs ACES → WebP vs ACES → BMP vs APNG → WebP vs APNG → BMP vs AVCI → WebP vs AVCI → BMP vs AVCS → WebP vs AVCS → BMP vs AVIF → WebP vs AVIF → All comparisons →
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