What is H.265 (HEVC)?
Definition
H.265, also called HEVC (High Efficiency Video Coding), is a video compression standard and the successor to H.264. It delivers similar visual quality at roughly 40-50% smaller file sizes, making it popular for 4K and high-resolution video.
H.265/HEVC compresses video more efficiently than H.264 by using larger, more flexible coding blocks and smarter motion prediction. The practical result is that you can store or stream the same-quality video at roughly half the bitrate, or get noticeably better quality at the same bitrate. This is why it became a common choice for 4K, HDR, and bandwidth-limited streaming.
The main trade-off is cost. H.265 is much heavier to encode and decode, so it needs more CPU power or dedicated hardware acceleration to play smoothly. It is also covered by patent-licensing pools, which makes support less universal than H.264 - especially in web browsers, where playback is often not guaranteed. H.264 remains the safest choice for maximum compatibility.
A common mistake is confusing the codec with the container. H.265 is a codec (how the video is compressed), while MP4 or MKV are containers (the file wrapper). HEVC and H.265 are two names for the exact same standard. Newer codecs like AV1 and H.266/VVC aim to beat H.265 on efficiency, but H.265 remains widely used in 2026.
Quick facts
- Also known as HEVC (High Efficiency Video Coding)
- Successor to H.264/AVC
- Roughly 40-50% smaller files at similar quality vs H.264
- Popular for 4K and HDR video
- Heavier to encode and decode, with less universal support due to patent licensing