Free webp to jpg
EN
Image MIME Reference
APNG

Animated Portable Network Graphics

image/vnd.mozilla.apng
VS

Free Lossless Image Format

image/flif
FLIF

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

APNG wins on browser support

Feature Support

Feature APNG FLIF
Transparency (Alpha) Yes Yes
Animation Support Yes Yes
Progressive Loading Yes Yes
HDR Support ✕ No Yes
EXIF Metadata Yes Yes
ICC Color Profile Yes Yes
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 →
Free Lossless Image Format
image/flif
Extension
.flif
Container FLIF Bitstream
Compression Lossless (MANIAC Entropy Coding)
Algorithm
MANIAC (Meta-Adaptive Near-zero Integer Arithmetic Coding)
Color Depth 1-bit to 16-bit (Per Channel), Grayscale, RGB, RGBA, CMYK
Developed by Jon Sneyers and Pieter Wuille (Cloudinary)
Released 2015
Magic Bytes
46 4C 49 46
Full FLIF reference →

Browser Support Comparison

Browser APNG FLIF
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)
FLIF

FLIF Strengths

  • Achieves some of the highest lossless compression ratios ever developed for raster images
  • Incredible progressive decoding allows an image to be highly recognizable even after only 5% of the file has been downloaded
  • Supports animations and complex alpha channels losslessly
Limitations
  • Officially abandoned in favor of JPEG XL
  • Zero native support in web browsers or standard operating system previewers
  • Encoding speed can be significantly slower than standard PNG or WebP compression

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
FLIF
Use FLIF when…
  • Archival of Uncompressed Image Assets
  • Bandwidth-Constrained Progressive Image Loading (Historical)
  • Medical and Scientific Imaging Storage

More comparisons

APNG vs ACES → FLIF vs ACES → APNG vs AVCI → FLIF vs AVCI → APNG vs AVCS → FLIF vs AVCS → APNG vs AVIF → FLIF vs AVIF → All comparisons →
Share this comparison