H264 vs H265 vs AV1: Which Video Codec Should You Use?

H264 vs H265 vs AV1 is the comparison behind many a stuttering video. A codec is the method that shrinks a video so it can be stored and streamed, then restores it when you press play. If a file opens on one device but not on another, if you hear sound with no picture, or if a 4K clip lags, a codec is almost always involved. This guide explains what codecs are, compares H.264, H.265 (HEVC), VP9 and AV1, shows why hardware decoding matters, and helps you pick the right one.

What is a video codec?

A codec, short for coder-decoder, is the algorithm that compresses video and later decompresses it for playback. The compressing half is the encoder, and the decompressing half is the decoder. The encoder runs once when the file is made; the decoder runs on your device every time you watch. Both sides must speak the same codec.

Audio has its own codecs, such as AAC, AC-3, Opus, FLAC and DTS. This article covers the picture side, but remember that a file plays only if both its video and its audio codec are supported.

Why do we need video codecs, and how do they work?

We need codecs because uncompressed video is enormous. Do the math: one 1920x1080 frame takes about 3.1 megabytes (1.5 bytes per pixel in standard 4:2:0 color). At 60 frames per second that is roughly 187 megabytes every second, or about 1.5 gigabits. No home connection carries that, yet a 1080p stream encoded with H.264 plays on a few megabits, hundreds of times less.

Codecs get there with three tricks. Intra-frame compression avoids storing every similar pixel in a frame, such as a patch of sky. Inter-frame compression notes that consecutive frames look alike and stores only what changed. Perceptual coding throws away detail the eye is unlikely to notice. Because of this, video codecs are lossy: at a high enough bitrate you cannot see the loss, and at a low one it shows up as blocky artifacts. Our guide to bitrate, resolution and frame rate explores that trade-off.

Is a codec the same as a container?

No. A container bundles video, audio and subtitles into one file, while a codec compresses each of those streams. MP4 and MKV are containers; H.264 and AV1 are codecs. An MKV file can hold H.264 or AV1. We separate the two ideas in MP4 vs MKV and handle everyday problems in how to open MKV files.

What are the main video codecs?

Four codecs dominate today: H.264, H.265, VP9 and AV1. Two come from the MPEG and ITU standards family, and two from Google and an open industry alliance.

H.264 (AVC)

H.264, also called AVC or MPEG-4 Part 10, was standardized in 2003 and is still the most widely used video codec in the world. It is found on Blu-ray discs, in camera recordings, on streaming services and in phone videos, and nearly every device has a hardware decoder for it. Its weakness is efficiency: it needs a higher bitrate than newer codecs for the same quality. Also note that 10-bit H.264 (Hi10P) is missing from most hardware decoders, which is why some files misbehave. See the Advanced Video Coding article for details.

H.265 (HEVC)

H.265, formally High Efficiency Video Coding (HEVC), arrived in 2013 and delivers similar visual quality to H.264 at roughly 25 to 50 percent lower bitrate, depending on the content and the encoder. It is the workhorse of 4K and HDR video, since the 10-bit color needed for HDR10 pairs naturally with it. Licensing is complicated because several patent pools are involved. Read more on the HEVC article.

VP9

VP9 is a royalty-free codec developed by Google and finalized around 2013. Its efficiency is in the same class as HEVC. Large video platforms such as YouTube use it, and you will usually meet it inside WebM files, which most browsers support.

AV1

AV1 is a royalty-free codec created by the Alliance for Open Media (AOMedia), with its specification finalized in 2018. It usually matches the quality of HEVC and VP9 at a lower bitrate. The price is much slower encoding and a need for a hardware decoder for smooth playback. The AOMedia website is the official source, and the AV1 article gives a neutral overview. H.266 (VVC) was completed in 2020, but adoption is only starting.

H.264 vs H.265 vs VP9 vs AV1: comparison table

The four codecs trade compatibility against efficiency: H.264 is the most compatible, AV1 the most efficient. Here is the summary.

H.264, H.265, VP9 and AV1 compared

Feature	H.264 (AVC)	H.265 (HEVC)	VP9	AV1
Developed by	ITU-T and ISO/IEC	ITU-T and ISO/IEC	Google	Alliance for Open Media
Released	2003	2013	About 2013	2018
Efficiency at similar quality	Baseline	Roughly 25-50% less bitrate	Close to HEVC	Usually better than HEVC
Licensing	Patent pool, royalties	Several patent pools	Royalty-free	Royalty-free
Encoding speed	Fast	Slower	Medium	Slowest
Device support	Nearly universal	Most recent devices	Browsers and many TVs	Newer chips
Typical containers	MP4, MKV, TS	MP4, MKV	WebM, MKV	MP4, MKV, WebM
Typical use	General video, cameras, Blu-ray	4K and HDR	Web video	Next-generation streaming and archives

The percentages are rough ranges that vary with content, encoder and settings; they are not guarantees.

What is hardware decoding, and why does it matter?

Hardware decoding means a dedicated circuit in the chip decodes the video instead of the main processor, which uses less power and decides whether heavy 4K video plays smoothly. Software decoding leaves the work to the CPU: it is flexible, but it costs battery and heat. If a phone or TV box has a hardware decoder for a codec, that codec plays easily; if not, you get stutter, dropped frames and fast battery drain.

That is why "why does this file lag on my old TV?" is so often answered by a newer codec. H.264 is hardware-decoded almost everywhere, HEVC on most recent devices, and AV1 hardware decoders only began appearing in new chips around 2020, so older devices lack them. When shopping for a box, our Android TV box buying guide says what to check for codec support, and 4K HDR video playback explains the HDR side.

Which codec should you choose?

The right codec depends on who will watch and on what device. This table is a practical starting point.

Choosing a codec by situation

Situation	Suggestion	Note
Must open on every device	H.264 + AAC in MP4	The safest choice
Watching 4K and HDR	H.265 (10-bit)	TV and player must decode HEVC
Publishing royalty-free web video	VP9 or AV1	Check browser support
Saving archive space	H.265 or AV1	Encoding takes long
Old TV or old phone	H.264, 8-bit	Avoid 10-bit H.264

Streaming services often prepare the same video in several versions and pick one for each device automatically; adaptive bitrate streaming shows how that choice is made.

How can you find out which codec a file uses?

You can read a file's codec in seconds. In VLC, open the Tools menu and choose Codec Information to see the video and audio codecs. The free MediaInfo program gives a far more detailed report. If you prefer the command line, this FFmpeg-family command is enough:

ffprobe -hide_banner video.mkv

Look for lines such as "Video: hevc" or "Video: h264"; "Main 10" tells you the video is 10-bit. With that, you can check whether your device decodes it.

How does Alpa Player fit in with codecs?

Alpa Player is a free media player developed by Alpa Yazılım. It plays M3U and M3U8 playlists, HLS streams, MP4, MKV and RTSP sources, and more. As with any player, how smoothly a given file plays also depends on your device's decoders. On Android the default engine is based on ExoPlayer (Media3), and you can choose a VLC engine or an external player. The ExoPlayer vs VLC comparison explains the differences.

Download Alpa Player for free for Android, Android TV, Samsung TV, LG TV, Fire TV and Windows; store versions are still being released. If playback stutters, our video buffering fixes give a checklist. Alpa Player supplies no content, so play only sources you have the right to use.