Why H.264 is everywhere
Nearly every chip made in the last fifteen years can decode H.264 in hardware, so playback is smooth and uses little battery. Every streaming protocol, player and DRM system supports it. A service that encodes in H.264 can be sure the video will play.
Profiles and levels
A level, such as 4.0 or 5.1, caps resolution, frame rate and bitrate. Lower rungs of a ladder are sometimes encoded with a more modest profile and level so that older devices can play them.
- Baseline: the simplest tools, for very old or low-power devices
- Main: the standard for most streaming renditions
- High: the most efficient, used for HD renditions
H.264 vs H.265 and AV1
The newer codecs reach the same quality at much lower bitrates: H.265 at roughly 40% to 50% less, AV1 at less again. H.264's advantages are universal playback, fast and inexpensive encoding, and simple licensing for streaming.
Its limits show at the top end. 4K in H.264 needs very high bitrates, and HDR is in practice delivered with newer codecs.
Typical H.264 bitrates
- 480p: about 1 to 2 Mbps
- 720p: about 2.5 to 4 Mbps
- 1080p: about 4 to 8 Mbps
Last reviewed