HEVC vs H.264: Which Video Codec Should You Use?

Should You Use HEVC or H.264?

High Efficiency Video Coding (HEVC, or H.265) gives about the same picture as H.264 at roughly half the bitrate. Verification tests reported by BBC R&D measured a 59% saving at equal perceived quality, and 44% with an objective metric. H.264 wins on compatibility: nearly every phone, browser and computer plays it, while HEVC needs newer devices and apps.

So the choice follows where the video goes. Keep the smaller format for storage on devices you control, such as your own recent iPhone. Use H.264 when someone else has to open the file and you don't know what they run.

Your iPhone saved a vacation clip in H.265, and the laptop you share it with shows a black frame with sound. That's the trade-off in one scene: less storage, and a player that can't decode it.

Video Codecs Explained: H.264 vs HEVC

A codec (the method that compresses and decodes video) does the video compression. It turns a huge stream of raw frames into something you can store and send.

A codec is not the same thing as the container. MP4 and MOV are containers: boxes that hold the video, the audio and some metadata. H.264 and H.265 are the codecs inside the box.

That's why two MP4s can behave differently. One holds H.264 and plays nearly everywhere. The other holds H.265 and fails on an older device.

H.264 is also known as Advanced Video Coding (AVC). Its other name, MPEG-4 AVC, comes from the Moving Picture Experts Group.

Technically, H.264 is a block-oriented, motion-compensation-based video compression standard.

In plain terms, the encoder cuts each frame into blocks. It describes most of them as "the same as in an earlier frame, moved a little." Only what changes costs many bits.

High Efficiency Video Coding (HEVC), also called H.265, is the successor. The need for smaller video at the same quality led to the development of a new standard.

HEVC refines the same block-and-motion approach with more advanced compression techniques. That's where the saving comes from, and it's also why encoding takes more work.

H.264 (AVC) vs HEVC (H.265): The Differences in Video Compression

The headline number is "50% smaller." It comes from the people who designed HEVC. Their IEEE paper reports that the new encoders reach equivalent subjective quality with about 50% less bitrate on average, on lower-resolution and HD test clips.

Formal verification tests by the joint team behind the standard, reported by BBC R&D, later checked the claim. They found an average saving of 59% at the same subjective quality, rated by human viewers.

With an objective metric (PSNR, a formula that compares pixels to the original), the saving dropped to 44%. The verification test paper in IEEE Transactions on Circuits and Systems for Video Technology gives the details.

Take "half the bit rate" as an average, not a promise for your clip. Video compression gains depend on what the clip holds and how it was encoded.

In practice, the edge in compression efficiency and video quality shows up two ways:

• Same quality, smaller size. H.265 can deliver the same video quality at about half the bitrate, so the size shrinks by about half too. Size is simply bitrate times duration.
• Same size, higher quality. Keep the bitrate and the newer codec spends the extra room on detail. That helps most on busy footage, where H.264 starts to break into blocks first.

Criterion	H.264 (AVC)	HEVC (H.265)
Bitrate for the same perceived quality	Reference	About 50% lower on average (59% subjective, 44% objective in the verification tests)
Decoding effort	Light	Not significantly heavier, per an analysis of the reference decoder
Encoding effort	Lower	Noticeably higher
Playback support	Nearly universal	Newer devices and apps
Where you meet it	Downloads, uploads, shared files	Recent iPhones, 4K recordings, storage

The practical rule stays simple. H.265 buys smaller video files, and you pay in compatibility.

Which Devices Actually Support HEVC

On Apple devices, the line is 2017. You need iOS 11 or macOS High Sierra, or later, to view, edit or duplicate this kind of video. That's the requirement on Apple's HEIF and HEVC support page.

Recording is a separate question. An iPhone 7 or later can record in H.265.

So can the iPad (6th generation), iPad Air (3rd generation), iPad mini (5th generation) and 10.5-inch iPad Pro, or newer. Older models keep recording in H.264.

Apple presents the format as the same visual quality in less storage space. It also offers a camera setting called Most Compatible, which records in H.264 instead. That setting exists for one reason: other devices and platforms don't all read it.

On Android, the H.264 decoder is listed as supported with no minimum version. The H.265 decoder is listed only from Android 5.0. Even then, the level listed for phones (Main Profile Level 3, a cap on the resolution and bitrate the decoder must handle) is lower than for Android TV (Level 4.1).

H.264 is widely supported because it had a long head start. H.265 now plays on a wider range of hardware than it once did, but "most" is not "all." When you send a clip to someone whose setup you don't know, H.264 is still the safe bet.

HEVC on Android: Automatic Conversion, Not Guaranteed

Android 12 added a fix for videos that apps can't read. The system can convert a video recorded in H.265 to H.264 when an app that doesn't support it opens the clip.

There are two catches. First, this compatible media transcoding is off by default, and the app's developer has to turn it on. Android's developer guide on media transcoding says so directly. An app that never opted in simply gets the original.

Second, the conversion takes time. Android's own figure: about 20 seconds to transcode one minute of H.265 video on a Pixel 3.

So a phone on Android 12 doesn't make the format safe to share. It depends on the app, and older Android versions don't have the feature at all.

Encoding Costs More CPU Than Decoding

HEVC's reputation as "heavy" is mostly about encoding. An analysis of the reference decoder found its complexity not significantly different from an H.264 decoder. Software playback is practical on common hardware.

Encoding is where the newer codec demands more processing power. The encoder tests more ways to split and predict each frame, and those extra choices cost time. If you export video, an H.265 export usually takes longer than H.264 at a similar preset.

For a viewer, the computational requirements are close. For whoever encodes, whether a creator or a streaming platform, they are not. Each step in the evolution of video codecs follows that pattern. Newer codecs such as AV1 ask even more of the encoder.

Real-World Applications and Usage Scenarios

Phone recordings. A recent iPhone records in H.265 unless you switch to Most Compatible. On the phone, that's the right call: less storage for the same picture. The trouble starts when the file leaves the Apple ecosystem, or reaches a device running older software.

Sharing and uploads. When you don't control the playback device, H.264 is the default that works. Email attachments, shared drives, a client's laptop, an older TV: H.264 in MP4 opens on all of them. If an iPhone clip won't open elsewhere, you can convert an iPhone MOV file to MP4 with H.264 inside.

Streaming. Streaming services pay for the bandwidth they use to send video content over the internet. Half the bitrate at the same quality means less bandwidth per viewer, making it possible to stream a sharper picture on a slow connection. But a service can only send H.265 to devices that decode it, so H.264 stays in the mix as the fallback.

Archives. For a personal archive of high-definition video, H.265 saves real disk space. Check that the devices you'll use later can play it, and keep an H.264 copy of anything you'll need to share.

Converting an HEVC File to H.264

Changing the extension doesn't change the codec. An H.265 video renamed from .mov to .mp4 is still H.265, and a device that can't decode it still fails. The fix is a re-encode to H.264.

A re-encode is lossy: the converter decodes the video and compresses it again as H.264. At a sensible quality setting, the loss is hard to see. Expect a bigger result, since H.264 needs more bitrate for the same picture.

You can convert HEVC to H.264 in your browser with Vidmini. It reads H.265 on most recent devices and writes H.264 video with AAC audio in an MP4.

Nothing is uploaded: the conversion runs on your device, with no account and no watermark. Chrome and Edge decode the widest range of codecs.

One caveat: HDR clips from recent iPhones can look slightly washed out after the re-encode.

Questions About HEVC and H.264

Which is better for iPhone videos, H.264 or HEVC?

H.265, as long as the video stays on Apple devices running iOS 11 or macOS High Sierra or later. It keeps the same visual quality in less storage. If you often send clips to other devices, the Most Compatible setting records in H.264 from the start.

Can I convert HEVC to H.264 without losing quality?

Not strictly. Switching codecs means a re-encode, and every re-encode loses some information. With a high quality setting, the difference is usually hard to spot, but the H.264 version ends up larger.

Do social media platforms accept HEVC uploads?

Upload rules differ by platform and change over time, so check the platform's own help page. If an upload fails or looks broken, try again with an H.264 MP4. It's the format the widest range of devices and platforms read.