AV1 vs H.264: Compare Quality, Size, Speed, and Fit

TL;DR

AV1 generally delivers better image quality than H.264 at the same bitrate, or similar quality with a smaller file. It is a strong choice for bandwidth-sensitive, high-resolution, and on-demand video.

H.264 remains the safer default when broad device compatibility, fast encoding, and predictable real-time performance matter most. For video calls and interactive live streaming, its extensive hardware support often outweighs AV1’s compression advantage.

The practical answer is not that one codec always wins: use AV1 where client support and encoding capacity are known, and retain H.264 as a compatibility fallback.

Understanding the AV1 and H.264 Codecs

Both codecs reduce the amount of data required to store or transmit video. Their main difference is the tradeoff they make among compression efficiency, processing cost, compatibility, and licensing.

H.264: The Proven, Widely Supported Standard

H.264, also called Advanced Video Coding or AVC, was standardized in 2003 by the ITU-T and ISO/IEC. It became the default codec for web video, broadcasting, Blu-ray, security cameras, conferencing, and mobile recording.

Its longevity is not its only advantage. H.264 can encode and decode efficiently, and hardware acceleration is available on almost every modern phone, computer, smart TV, and streaming device. That broad support reduces playback failures and limits CPU and battery consumption.

H.264’s weakness is compression efficiency compared with newer codecs. To preserve the same visual quality, it will usually require a higher bitrate than AV1. That means larger files, greater bandwidth consumption, or both.

AV1: A More Efficient Modern Codec

AV1 was developed by the Alliance for Open Media and released in 2018. It was designed as an open, royalty-free codec for internet video, including high-resolution streaming.

AV1 uses more advanced prediction and partitioning techniques to compress frames efficiently. This can produce cleaner video at constrained bitrates or reduce delivery costs while maintaining a similar quality target. Those benefits become particularly valuable for 4K content, large streaming catalogs, and viewers on limited connections.

The tradeoff is computational complexity. Software-based AV1 encoding can be much slower than H.264, especially when configured for maximum efficiency. Hardware AV1 encoding and decoding are improving, but support remains less universal than H.264.

AV1 vs. H.264: A Feature-by-Feature Comparison

The right codec depends on where the video is produced, how quickly it must be delivered, and which devices must play it.

Decision factor	AV1	H.264
Compression efficiency	Higher	Lower
File size at comparable quality	Usually smaller	Usually larger
Software encoding speed	Generally slower	Generally faster
Real-time suitability	Good with supported hardware and tuned settings	Consistently strong
Device compatibility	Growing, but uneven on older devices	Nearly universal
Low-bitrate quality	Usually better	Acceptable, with more visible degradation
Licensing model	Designed to be royalty-free	Patent licensing may apply
Best fit	On-demand, high-resolution, bandwidth-sensitive video	Calls, live video, broad device reach

1. Compression Efficiency and File Size

In an AV1 vs. H.264 file size comparison, AV1 typically wins when both encoders target similar visual quality. Depending on the content, encoder, and preset, AV1 may require materially less bitrate than H.264.

However, percentages such as “30% smaller” should be treated as estimates rather than guarantees. Animation, screen sharing, sports, film grain, camera noise, and fast motion respond differently to compression. A slow AV1 preset may produce an impressive result, while a real-time AV1 preset may narrow the advantage.

File size is largely determined by bitrate and duration:

file size ≈ bitrate × duration

For example, ten minutes of video at 5 Mbps uses roughly 375 MB before accounting for audio and container overhead. Reducing the bitrate to 3.5 Mbps lowers that figure to about 263 MB. AV1’s value is its ability to make that reduction while preserving more visual detail.

For prerecorded video, the extra encoding time can be worthwhile because the file is encoded once but delivered many times. For a small internal video library, the storage savings may not justify replacing an established H.264 workflow.

2. Encoding Speed and Real-Time Performance

AV1’s additional compression tools require more computation. At quality-focused settings, software AV1 encoding can take substantially longer than H.264 encoding.

That is manageable for on-demand workflows. A platform can encode an uploaded video in the background, create several adaptive-bitrate renditions, and distribute them after processing finishes.

Real-time communication has a stricter deadline. A frame that takes too long to encode cannot simply arrive later without increasing latency. Video calls, interactive broadcasts, and cloud gaming therefore need fast encoding with stable frame times—not only efficient compression.

Modern AV1 hardware encoders make live use increasingly practical, but deployment still depends on the sender’s device, browser, operating system, and power budget. H.264 has mature hardware acceleration across a much larger installed base, making it the more predictable option for heterogeneous audiences.

When evaluating real-time AV1, test end-to-end latency and CPU/GPU usage instead of relying only on offline quality benchmarks.

3. Decoding Demands and Device Compatibility

A codec is useful only if the intended audience can decode it reliably.

AV1 playback support has expanded across current browsers, televisions, GPUs, and mobile processors. Yet software decoding may still increase CPU usage on devices without AV1 hardware acceleration. At high resolutions, this can cause dropped frames, heat, battery drain, or playback failure.

H.264 decoding is built into almost every relevant device category. It is especially valuable when an application must support older phones, embedded browsers, low-cost computers, or enterprise-managed hardware.

Compatibility should be tested at three levels:

1. Codec recognition: Can the browser or operating system identify the stream?
2. Hardware acceleration: Can it decode without excessive CPU and battery use?
3. Resolution and profile support: Can it handle the exact profile, level, frame rate, and resolution you plan to send?

For public-facing services, the safest approach is often AV1 where capability detection confirms support, with H.264 available as a fallback.

4. Licensing and Royalty Considerations

AV1 was designed to be royalty-free, which can simplify adoption for platforms distributing large volumes of video. Its open specification also supports broad implementation without relying on one commercial codec vendor.

H.264 is covered by patents, and licensing obligations may apply depending on the implementation, distribution model, region, and use case. Many teams use H.264 through operating systems, browsers, or licensed hardware without handling codec royalties directly, but that does not make every commercial scenario automatically royalty-free.

Codec licensing is a legal and business question as well as a technical one. Organizations shipping encoders, decoders, paid content, or hardware products should review current terms with qualified counsel rather than making a decision from a general comparison alone.

5. Quality at Equal and Low Bitrates

For an AV1 vs. H.264 video quality comparison, the fairest test uses the same source, resolution, frame rate, and bitrate. Under those conditions, AV1 will generally preserve more detail and show fewer compression artifacts.

At low bitrates, H.264 is more likely to exhibit:

• Blocking in flat backgrounds
• Smearing during motion
• Lost texture in hair, foliage, or fabric
• Banding in gradients
• Reduced clarity around text and edges

AV1 usually manages these difficult areas more effectively. This makes it attractive for mobile viewing, constrained networks, and adaptive-bitrate streaming, where every saved bit matters.

Still, codec name alone does not determine quality. Encoder implementation and configuration can outweigh the format advantage. A carefully tuned H.264 encode may look better than a rushed AV1 encode using an aggressive real-time preset.

For a useful AV1 vs. H.264 bitrate test, compare multiple clips representative of your product. Include faces, motion, screen content, low-light footage, and network-induced bitrate reductions. Evaluate visual quality alongside encoding latency, dropped frames, and device power consumption.

Choosing Between AV1 and H.264

If you are asking “AV1 vs. H.264—which is better?”, start with the delivery context rather than compression efficiency alone.

Choose AV1 when:

• Reducing bandwidth or storage is a priority. Smaller streams can lower delivery costs and improve playback on constrained connections.
• You publish prerecorded content. Longer encoding time is easier to absorb when assets are encoded once and watched repeatedly.
• Low-bitrate quality matters. AV1 tends to retain more useful detail as available bandwidth falls.
• Your audience uses supported devices. Capability detection or a controlled hardware environment reduces compatibility risk.
• You need an open, royalty-free codec design. This can simplify the economics of large-scale distribution, subject to your legal review.
• You are preparing a long-lived media library. AV1 is well suited to modern high-resolution delivery.

Choose H.264 when:

• Maximum compatibility is essential. It remains the lowest-risk choice for mixed browsers, phones, televisions, and older hardware.
• Your application is latency-sensitive. Calls and interactive broadcasts benefit from its mature real-time hardware pipeline.
• Encoding resources are limited. H.264 generally requires less computation, particularly without dedicated AV1 hardware.
• You cannot control the receiving devices. Public links and bring-your-own-device environments favor a widely supported codec.
• Fast deployment matters more than delivery optimization. Existing H.264 tooling, expertise, and infrastructure can shorten implementation time.

Many production systems do not make an absolute choice. They use AV1 for supported on-demand or high-bandwidth-cost scenarios and H.264 for compatibility-sensitive delivery. Real-time applications should also account for network adaptation, congestion control, packet loss recovery, and device performance; codec efficiency cannot compensate for a weak transport pipeline.

How to Build an App Like This with Tencent RTC

For a custom calling, conferencing, or interactive streaming application, use Tencent RTC Engine as the real-time media layer. It provides cross-platform room communication, low-latency transport, weak-network resilience, media processing, and operational monitoring.

A practical architecture has four parts:

1. Application server: Authenticates the user and generates a short-lived userSig. Never place the signing secret in browser code.
2. Capability and codec policy: Detects supported client capabilities and defines compatibility requirements. H.264 is the conservative baseline; only depend on AV1 after validating support across your target platforms and current SDK controls.
3. Tencent RTC room: Routes real-time audio and video among participants while handling network adaptation.
4. Web or native clients: Capture local media, publish it after entering the room, and subscribe to remote streams.

Follow the Tencent RTC Engine overview and integration guidance, then install trtc-sdk-v5 for a web implementation. The high-level build sequence is:

1. Create a Tencent RTC application and obtain its SDKAppID.
2. Generate userSig securely on your backend.
3. Create the client and register remote-media events before room entry.
4. Enter a room with roomId, userId, and userSig.
5. Start local camera and microphone capture. In the web SDK, these local-media calls publish the tracks in the active room.
6. Subscribe and render video when another participant publishes.
7. Test weak networks, older devices, CPU load, and codec fallback behavior before release.

import TRTC from "trtc-sdk-v5";

const trtc = TRTC.create();

trtc.on(
  TRTC.EVENT.REMOTE_VIDEO_AVAILABLE,
  async ({ userId, streamType }) => {
    const viewId = `remote-${userId}-${streamType}`;

    await trtc.startRemoteVideo({
      userId,
      streamType,
      view: viewId
    });
  }
);

const { userSig } = await fetch(
  "/api/rtc-credentials?userId=alice"
).then((response) => response.json());

await trtc.enterRoom({
  roomId: 8888,
  sdkAppId: 1400000000,
  userId: "alice",
  userSig
});

// Capture and publish local media after room entry.
await trtc.startLocalVideo({ view: "local-video" });
await trtc.startLocalAudio();

Do not assume that selecting AV1 automatically improves a call. Measure join success, encode time, CPU usage, frame rate, glass-to-glass latency, and quality under packet loss. If your audience includes unknown or older devices, prioritize reliable room entry and H.264-compatible delivery over a theoretical bitrate advantage.

FAQ

Does AV1 look better than H.264?

Usually, yes, when both use the same bitrate and comparable encoder settings. AV1 generally preserves more detail and introduces fewer artifacts, especially at low bitrates.

How much smaller is AV1 than H.264?

AV1 files are often materially smaller at similar visual quality, but there is no universal percentage. Results depend on the source content, encoder, preset, resolution, and quality target.

Is AV1 or H.264 better for video calls?

H.264 is still the safer default for calls because of its broad hardware support and predictable real-time performance. AV1 can be valuable on supported devices, but it should be introduced with capability checks, performance testing, and fallback support.