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

The Codec Decision That Shapes Every Pixel

Video codecs sit at the core of every video file you create, share, or watch. They determine how much storage your footage demands, how quickly it loads over a network, and whether it plays on a given device at all. The three codecs that matter most in 2026 are H.264, H.265 (also called HEVC), and AV1 -- and each one represents a different generation of compression technology with distinct trade-offs.

H.264 has been the universal standard for two decades. H.265 promised to cut file sizes in half while maintaining the same quality. AV1, backed by the Alliance for Open Media, aims to match or beat H.265 without the licensing complexity. Understanding the strengths and limitations of each codec helps you make informed decisions whether you are preparing content for YouTube, archiving personal footage, or optimizing video for a website.

This guide provides a thorough, practical comparison. If you want a broader overview of how codecs relate to container formats like MP4, WebM, and MKV, the video codecs explained post covers the fundamentals in detail.

Quick Comparison Table

This table captures the key differences at a glance. The sections that follow break down each factor in depth.

H.264: The Universal Standard

Why H.264 Still Dominates

H.264, formally known as Advanced Video Coding (AVC), was finalized in 2003 and rapidly became the default codec for nearly everything: Blu-ray discs, streaming platforms, video conferencing, security cameras, and web video. Its dominance stems from one thing above all else -- compatibility. Every smartphone, browser, smart TV, game console, and media player released in the past fifteen years can decode H.264 without breaking a sweat.

Hardware encoder and decoder chips for H.264 are embedded in virtually every piece of silicon that touches video. This means encoding is fast and power-efficient, and playback drains minimal battery life. For creators who need a file that "just works" everywhere, H.264 inside an MP4 container remains the safest choice. You can convert any video to this combination using the MP4 converter.

Where H.264 Falls Short

The problem with H.264 is its age. It was designed before 4K content, HDR, and ultra-high-bitrate streaming became mainstream. At 4K resolution, H.264 produces files roughly twice the size of what H.265 or AV1 would generate at equivalent visual quality. For high-resolution workflows -- drone footage, cinematic content, archival -- this means significantly more storage and bandwidth consumption.

H.264 also lacks native support for modern HDR standards. While you can technically encode HDR10 metadata into an H.264 stream, no major player or platform supports this combination in practice. If your workflow involves HDR content, you need H.265 or AV1.

H.264 Encoding Profiles

H.264 defines several profiles that control the encoding complexity and feature set:

• Baseline -- Simple encoding, used for low-power devices and video conferencing
• Main -- Standard definition broadcast and streaming
• High -- Full HD content, Blu-ray, mainstream streaming
• High 10 -- 10-bit color depth for professional workflows

Most modern usage targets the High profile at Level 4.1 or 5.1 depending on resolution.

H.265 (HEVC): The Compression Leap

How H.265 Achieves 50% Smaller Files

H.265, or High Efficiency Video Coding (HEVC), was designed specifically to address H.264's limitations at higher resolutions. The key technical advancement is larger coding tree units (CTUs). Where H.264 processes video in 16x16 pixel macroblocks, H.265 uses flexible blocks up to 64x64 pixels, allowing the encoder to handle large uniform areas -- like sky or walls -- far more efficiently.

The result is striking. At the same visual quality, H.265 typically produces files 40-50% smaller than H.264. For a 4K video that would be 5 GB in H.264, H.265 might produce a 2.5-3 GB file that looks identical to the human eye. This compression advantage is the reason Netflix, Apple TV+, and most major streaming platforms adopted H.265 for their 4K catalogs.

The Licensing Problem

H.265's Achilles heel is its licensing structure. Unlike H.264, which has a single licensing body (MPEG LA), H.265 patents are split across multiple pools: MPEG LA's HEVC patent pool, Access Advance (formerly HEVC Advance), and additional patents held by companies that belong to neither pool. This fragmentation creates legal uncertainty for companies that want to deploy H.265 at scale.

The licensing situation directly affected browser support. Google chose not to pay H.265 royalties for Chrome, instead backing the royalty-free VP9 and later AV1. Mozilla followed suit with Firefox. As a result, H.265 browser playback is inconsistent -- it works in Safari (Apple pays the licenses) and in Edge and Chrome on devices with hardware decoding, but software decoding in browsers remains patchy.

When to Choose H.265

H.265 excels in scenarios where you control the playback environment:

• 4K and 8K content where file size and bandwidth matter
• Streaming services with dedicated apps (not browser-only)
• Archival storage where you want maximum quality per gigabyte
• Apple ecosystem workflows where HEVC is the default capture codec
• Security camera systems that need efficient 24/7 recording

For converting between containers while preserving your H.265 streams, the MKV converter supports lossless remuxing.

AV1: The Open-Source Future

What Makes AV1 Different

AV1 was developed by the Alliance for Open Media (AOM), a consortium that includes Google, Apple, Amazon, Microsoft, Netflix, Meta, and other major technology companies. Its defining feature is that it is completely royalty-free. Any company or individual can encode, decode, and distribute AV1 content without paying licensing fees.

From a compression standpoint, AV1 matches or slightly exceeds H.265 in most benchmarks. Independent tests consistently show AV1 producing files 20-30% smaller than H.265 at equivalent quality, and 50-60% smaller than H.264. This makes AV1 the most efficient widely-deployed codec available today.

The Encoding Speed Trade-Off

AV1's biggest practical limitation is encoding speed. The reference encoder (libaom) is notoriously slow -- often 10-20 times slower than H.264 encoding and 5-10 times slower than H.265. This makes AV1 impractical for real-time encoding or scenarios where fast turnaround matters.

However, this situation has improved significantly. SVT-AV1, developed by Intel and Netflix, offers dramatically faster encoding with only modest quality penalties compared to libaom. Hardware AV1 encoders in newer GPUs (NVIDIA RTX 40-series, Intel Arc, AMD RX 7000-series) bring encoding speeds close to H.265 hardware encoding. Apple's M3 and later chips include hardware AV1 encoding as well.

Browser and Device Support

AV1 browser support has reached a tipping point. Chrome, Firefox, and Edge have supported AV1 decoding for several years. Safari added AV1 support starting with Safari 17 on macOS Sonoma and iOS 17, though only on devices with hardware decode capability (M1 and later Macs, A17 Pro and later iPhones).

On the hardware side, AV1 decode support exists in:

• NVIDIA GPUs from the RTX 30-series onward
• AMD GPUs from the RX 6000-series onward
• Intel GPUs from 11th-gen (Tiger Lake) onward
• Apple M1 and later chips
• Qualcomm Snapdragon 888 and later
• MediaTek Dimensity 1000 and later

This means most devices sold since 2021 can decode AV1 efficiently.

Detailed Feature Comparison

Quality vs File Size at Different Resolutions

The efficiency gap between codecs widens as resolution increases. At 480p, the difference between H.264 and AV1 is modest. At 4K, it becomes dramatic.

These are approximate values for comparable visual quality using standard encoding presets. Actual results vary with content complexity, encoder settings, and specific implementations.

Hardware Decode and Encode Support

Hardware acceleration determines whether a device can play or encode video without taxing the CPU. This table covers common platforms.

Use Case Recommendations

Social Media and Short-Form Content

For platforms like YouTube, Instagram, TikTok, and Twitter, H.264 in an MP4 container remains the recommended upload format. These platforms re-encode your video on their servers anyway, so uploading in the most compatible format avoids any transcoding artifacts in the intermediate step. Read the best video formats for social media in 2026 for platform-specific guidance.

Web Embedding and Progressive Delivery

If you are embedding video directly on a website (not through YouTube or Vimeo), AV1 in WebM offers the best bandwidth savings for most visitors. Implement a fallback strategy using the HTML <source> element:

<video controls>
  <source src="video.webm" type="video/webm; codecs=av01.0.05M.08" />
  <source src="video.mp4" type="video/mp4" />
</video>

The browser will use the AV1 WebM if supported and fall back to H.264 MP4 otherwise. The video converter category page lists all available format conversions.

Archival and Long-Term Storage

For archiving footage that you want to preserve at the highest quality with reasonable file sizes, H.265 in an MKV container is the current sweet spot. MKV supports virtually any codec and allows multiple audio tracks, subtitles, and chapters. H.265 offers the best combination of mature tooling, widespread hardware support, and compression efficiency for archival purposes.

Streaming and OTT Platforms

Professional streaming services typically offer multiple codec ladders. A modern approach is:

1. H.264 for legacy devices and low-bandwidth connections
2. H.265 for 4K HDR content on smart TVs and mobile apps
3. AV1 for web browsers and newer devices

This multi-codec strategy ensures maximum reach while delivering the best possible quality to each viewer segment.

Video Editing and Production

For editing workflows, codec choice depends on your NLE (Non-Linear Editor). Most editors handle H.264 efficiently. H.265 editing performance varies -- Final Cut Pro handles it well thanks to Apple's hardware acceleration, but Premiere Pro and DaVinci Resolve may struggle with H.265 on systems without dedicated hardware decoders. AV1 editing support is still limited in most professional editors.

For smooth editing performance, many professionals use intermediate codecs (ProRes, DNxHR) during editing and export to H.264, H.265, or AV1 only for final delivery.

Converting Between Codecs

Converting video from one codec to another is a common workflow, whether you are optimizing older H.264 content for modern delivery or making H.265 footage compatible with a broader range of devices.

Key considerations when transcoding:

• Quality loss is cumulative. Each encode-decode cycle introduces some degradation. Avoid transcoding the same file multiple times.
• Bitrate headroom matters. When converting from H.264 to H.265, you can target roughly half the bitrate for equivalent quality.
• Container compatibility varies. H.264 and H.265 work in MP4, MKV, and TS containers. AV1 works in MP4, WebM, and MKV. Verify your target container supports your chosen codec.
• Hardware encoding trades quality for speed. GPU-accelerated encoding is 5-10x faster but typically produces larger files at equivalent quality compared to software encoding.

You can convert videos between codecs directly using the MP4 converter for H.264 and H.265 output, the WebM converter for AV1 and VP9 output, or the MKV converter for any codec in a Matroska container.

The Royalty-Free Advantage of AV1

One of the most significant strategic differences between these codecs is licensing. H.264 requires royalties paid to MPEG LA. H.265 has an even more complex and expensive licensing landscape. AV1, by contrast, is completely royalty-free.

This matters beyond just cost. Royalty-free codecs encourage adoption. Google mandates AV1 support for new Android devices. Netflix uses AV1 for its mobile streams. YouTube serves AV1 to compatible browsers. The ecosystem momentum behind AV1 is accelerating precisely because there are no licensing barriers to entry.

For smaller companies, independent creators, and open-source projects, the royalty-free nature of AV1 removes legal complexity entirely. You can encode, host, and distribute AV1 content without worrying about patent claims or licensing fees.

Performance Benchmarks in Practice

Real-world encoding performance varies dramatically based on hardware, software encoder, and settings. Here are representative figures for encoding a 10-minute 1080p clip:

• H.264 (x264, medium preset): ~3 minutes on a modern 8-core CPU
• H.265 (x265, medium preset): ~12 minutes on the same hardware
• AV1 (SVT-AV1, preset 6): ~20 minutes on the same hardware
• AV1 (libaom, speed 4): ~90 minutes on the same hardware

Hardware encoding changes the equation significantly. An NVIDIA RTX 4080 can encode H.264, H.265, and AV1 in near-real-time, though with slightly lower compression efficiency than software encoders.

Future Outlook

H.266 (VVC) on the Horizon

The ITU-T and ISO have already finalized H.266, also known as Versatile Video Coding (VVC). It promises another 40-50% compression improvement over H.265. However, it inherits the same licensing complexity as its predecessor, and adoption has been slow. It is unlikely to displace AV1 for web delivery.

AV2 in Development

The Alliance for Open Media is developing AV2, which aims to deliver significant improvements over AV1 while maintaining the royalty-free model. Early testing shows promising results, but a final specification is still years away.

The Convergence Trend

In the near term, the industry is converging on a dual-codec strategy: H.265 for traditional broadcast and app-based streaming, and AV1 for web and mobile delivery. H.264 will continue to serve as the universal fallback for legacy devices. This three-tier approach maximizes both compatibility and efficiency.

How to Choose: Decision Framework

Selecting a codec comes down to answering a few key questions:

1. Who is your audience? If you need universal playback on any device, start with H.264. If your audience uses modern browsers, AV1 is viable. If they use smart TVs and streaming apps, H.265 works well.

2. What is your resolution? At 1080p and below, the compression advantage of newer codecs is real but modest. At 4K and above, the savings from H.265 or AV1 are substantial and can reduce costs significantly.

3. How fast do you need to encode? Real-time or near-real-time encoding favors H.264 or hardware-accelerated H.265. Batch encoding for VOD allows time for AV1's superior but slower compression.

4. Do licensing costs matter? For commercial products, AV1's royalty-free status is a significant advantage over both H.264 and especially H.265.

5. Is HDR required? H.265 and AV1 both support modern HDR standards. H.264 does not, effectively ruling it out for HDR workflows.

If your project involves video conversion, the video compressor tool handles the complexity of codec selection and parameter tuning automatically, letting you focus on results rather than encoding flags.

Common Misconceptions About Video Codecs

"Newer codecs always look better"

Not exactly. At very high bitrates, all three codecs produce visually identical results -- there simply is not enough room for compression artifacts. The advantage of newer codecs appears at moderate-to-low bitrates, where they can maintain quality with fewer bits. If storage and bandwidth are unlimited, H.264 at a high bitrate looks just as good as AV1.

"AV1 is too slow to be practical"

This was true in 2019-2020 but is increasingly outdated. Hardware AV1 encoding on modern GPUs (RTX 40-series, Intel Arc, Apple M3+) runs at near-real-time speeds. Software encoders like SVT-AV1 have also improved dramatically. For pre-encoded VOD content where encoding happens once and playback happens millions of times, even slower encoding is an excellent trade-off.

"H.265 is dying because of licensing"

H.265 is not going away. It dominates 4K Blu-ray, broadcast television, and streaming app delivery. Its ecosystem is deeply entrenched, and billions of hardware decoders exist in the field. What H.265 is unlikely to win is the open web, where royalty-free AV1 has the strategic advantage.

"You should always use the newest codec"

Context matters more than recency. A video meant for a digital signage screen running outdated firmware should use H.264. A 4K HDR film destined for a streaming app should use H.265. A web-embedded tutorial video should use AV1 with an H.264 fallback. Match the codec to the deployment environment.

Codec Selection by Platform

Different platforms have different codec preferences and requirements. Here is a quick reference for common destinations:

• YouTube -- Upload in H.264 (YouTube re-encodes to AV1 and VP9 server-side)
• Netflix -- AV1 for mobile, H.265 for TVs and apps
• Twitch -- H.264 for live streaming (hardware encoding recommended)
• Vimeo -- H.264 recommended for uploads
• Instagram / TikTok -- H.264 in MP4 (platform re-encodes)
• Twitter/X -- H.264 in MP4
• Personal website -- AV1 in WebM with H.264 MP4 fallback
• Email attachment -- H.264 in MP4 (smallest compatible file)
• Archival storage -- H.265 in MKV (best compression with mature tooling)

For platform-specific video specifications including resolution, aspect ratio, and bitrate recommendations, the best video format for social media guide provides detailed breakdowns.

Conclusion

There is no single "best" codec -- only the best codec for your specific situation. H.264 remains the safest default when compatibility is paramount. H.265 delivers meaningful compression gains for high-resolution content in controlled playback environments. AV1 offers the strongest compression and a royalty-free future, with the trade-off of slower encoding and still-maturing hardware support.

For most creators publishing to the web in 2026, a practical approach is to encode in H.264 for maximum compatibility today while adopting AV1 for progressive enhancement as browser and hardware support continues to expand. The best video formats guide provides additional context on how these codecs interact with container formats for different use cases.