Video Codec Comparison: H.264 vs H.265 vs VP9 vs AV1

Understanding Video Codecs

A codec (coder-decoder) compresses raw video into a manageable file size and decompresses it for playback. The codec determines quality-per-bit — better codecs produce smaller files at the same visual quality.

H.264 (AVC)

Released in 2003, H.264 remains the most widely supported codec. Every browser, device, and hardware decoder supports it. Encoding is fast and well-optimized after two decades of development.

Best for: Maximum compatibility, real-time encoding, legacy device support. Drawback: 30-50% larger files than newer codecs at equivalent quality.

H.265 (HEVC)

H.265 achieves roughly 50% better compression than H.264. However, it carries licensing fees and limited browser support — only Safari and Edge support it natively. Chrome and Firefox do not.

Best for: Apple ecosystem, 4K/HDR content, offline playback. Drawback: Patent licensing costs, poor browser support.

VP9

Google's royalty-free answer to H.265. VP9 achieves similar compression to HEVC and is supported in Chrome, Firefox, and Edge. YouTube uses VP9 extensively for its streaming pipeline.

Best for: Web delivery, YouTube, royalty-free workflows. Drawback: Slower encoding than H.264, no Safari support.

AV1

The newest codec, developed by the Alliance for Open Media. AV1 achieves 30% better compression than VP9 and is royalty-free. Browser support is growing (Chrome, Firefox, Safari 17+).

Best for: Future-proof delivery, maximum compression. Drawback: Very slow encoding (10-100x slower than H.264). Hardware encoders are still emerging.

Comparison Table

Practical Recommendation

For web delivery, encode in H.264 as a baseline with VP9 or AV1 as progressive enhancements. Use the HTML element with multiple tags to serve the best codec each browser supports.