VP9 Codec Guide
The open-source backbone of modern web video.
The Open Source Alternative
Developed by Google, VP9 was explicitly designed to match the efficiency of HEVC while remaining royalty-free. By avoiding the patent disaster of HEVC, VP9 gained immediate and universal support in Chrome, Firefox, and the entire Android ecosystem.
Today, almost all YouTube video is delivered in VP9 to supported browsers.
Performance vs HEVC
Objectively, HEVC is slightly more efficient than VP9 (saving perhaps 5-10% more bitrate at identical VMAF scores), but VP9 encoding (via `libvpx`) is often faster and better optimized for x86 CPUs than HEVC encoders were in their early days.
Common Mistakes
- Expecting Apple support: Apple explicitly ignored VP9 for years because they backed HEVC. While newer macOS/iOS versions have added some VP9 support (primarily to allow 4K YouTube playback), you cannot rely on VP9 for native Apple apps; you must provide an HLS HEVC or H.264 stream.
FAQ
Many massive platforms do exactly this: they serve HEVC to Apple devices and VP9 to Chrome/Android devices. This ensures maximum bandwidth savings across the board, but it doubles your encoding and storage costs. For most mid-sized platforms, it is better to skip VP9, use H.264 as a baseline, and invest directly in AV1 for the future.