Free webp to jpg
EN
Image MIME Reference
APNG

Animated Portable Network Graphics

image/vnd.mozilla.apng
VS

Wireless Bitmap

image/vnd.wap.wbmp
WBMP

A complete technical comparison of Animated Portable Network Graphics and Wireless Bitmap — covering compression, feature support, browser compatibility, magic bytes, and when to choose each format.

APNG wins on browser support

Feature Support

Feature APNG WBMP
Transparency (Alpha) Yes ✕ No
Animation Support Yes ✕ No
Progressive Loading Yes ✕ No
HDR Support ✕ No ✕ No
EXIF Metadata Yes ✕ No
ICC Color Profile Yes ✕ No
Animated Portable Network Graphics
image/vnd.mozilla.apng
Extension
.apng.png
Container PNG Chunk Stream
Compression Deflate (Lossless)
Algorithm
Deflate (zlib)
Color Depth 8-bit (Indexed), 24-bit (TrueColor), 32-bit (RGBA)
Developed by Mozilla Corporation (Stuart Parmenter & Vladimir Vukićević)
Released 2004
Magic Bytes
89 50 4E 47 0D 0A 1A 0A
Full APNG reference →
Wireless Bitmap
image/vnd.wap.wbmp
Extension
.wbmp
Container WBMP Type 0
Compression Uncompressed
Algorithm
None
Color Depth 1-bit (Monochrome)
Developed by WAP Forum (Now Open Mobile Alliance)
Released 1999
Magic Bytes
00 00
Full WBMP reference →

Browser Support Comparison

Browser APNG WBMP
Chrome Chrome
✓ 59
 ✕
Firefox Firefox
✓ 3
 ✕
Safari Safari
✓ 8
 ✕
Edge Edge
✓ 79
 ✕
IE IE (Legacy)
✕ ✕
APNG

APNG Strengths

  • Supports 8-bit alpha transparency, completely solving the ugly 'white halo' problem inherent to GIFs
  • Gracefully degrades; viewers that do not support APNG will render a perfectly valid, static PNG of the first frame
  • Provides lossless compression that retains absolute pixel-perfect quality for UI elements and line art
Limitations
  • Because it relies on lossless Deflate compression, file sizes for complex, video-like animations can be massive compared to lossy formats like WebP or AVIF
  • Was initially rejected by the official PNG group, delaying its adoption for nearly a decade
  • Lacks native hardware decoding acceleration, unlike video-based animated formats (like MP4 or WebM)
WBMP

WBMP Strengths

  • Extremely low processing overhead made it perfectly suited for the ultra-low-power CPUs of late 1990s mobile devices
  • Tightly integrated into the WML (Wireless Markup Language) stack, enabling the first functional mobile internet experiences
Limitations
  • Completely obsolete and lacks support in modern operating systems and browsers
  • Limited entirely to 1-bit black and white (0 for black, 1 for white) with zero support for grayscale, color, or transparency
  • The lack of a strong file header signature makes automated MIME type detection highly unreliable

When to choose which format

APNG
Use APNG when…
  • High-Quality Web Animations
  • Stickers (Apple iMessage, LINE, Discord)
  • UI Loaders with Alpha Transparency
  • GIF Replacement
WBMP
Use WBMP when…
  • Legacy WML (Wireless Markup Language) Mobile Sites
  • Early Mobile Phone Icons and Operator Logos
  • Historical WAP Archival

More comparisons

APNG vs ACES → WBMP vs ACES → APNG vs AVCI → WBMP vs AVCI → APNG vs AVCS → WBMP vs AVCS → APNG vs AVIF → WBMP vs AVIF → All comparisons →
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