Free webp to jpg
Image MIME Reference
APNG

Animated Portable Network Graphics

image/vnd.mozilla.apng
VS

Extended Image File Format

image/vnd.xiff
XIFF

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

APNG wins on browser support

Feature Support

Feature APNG XIFF
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 →
Extended Image File Format
image/vnd.xiff
Extension
.xif
Container TIFF-based Proprietary Container
Compression CCITT Group 3 / Group 4 / LZW / Uncompressed
Algorithm
CCITT Group 4LZWNone
Color Depth 1-bit (Monochrome), 8-bit (Grayscale), 24-bit (RGB)
Developed by Keyfile Corporation
Released 1994
Magic Bytes
49 49 2A 00 or 4D 4D 00 2A
Full XIFF reference →

Browser Support Comparison

Browser APNG XIFF
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)
XIFF

XIFF Strengths

  • Pioneered early enterprise document workflow integration by binding administrative routing data directly to the document image file
  • Leveraged efficient fax compression standards to keep storage requirements low on 1990s server infrastructure
Limitations
  • Completely proprietary and obsolete; Keyfile Corporation's software ecosystem no longer exists
  • Causes widespread MIME type identification conflicts due to sharing the exact same binary header signature as standard TIFF files
  • Zero support in modern operating systems or web browsers

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
XIFF
Use XIFF when…
  • Keyfile Enterprise Document Management
  • Legacy Corporate Workflow Archival
  • Scanned Multi-page Document Routing
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