HEVC to MP4 Converter (H.265 to H.264)

HEVC (H.265) halves the size of video at the same quality, which is why iPhones, many Android phones, drones and cameras record in it. But older Windows PCs, smart TVs, some browsers and many editing and upload tools cannot play it. This converter turns HEVC into H.264 MP4, the format every device plays, converting HDR to standard range and 10-bit to 8-bit on the way. If an HEVC file already plays on Windows and Android but not on an iPhone or Mac — common with MKV or downloaded MP4s — the instant mode repackages it with the "hvc1" tag Apple needs, without re-encoding. It runs in your browser with the ffmpeg engine (about 30 MB, downloaded once).

How to use this tool

1. Choose one or more HEVC videos: iPhone MOV, MP4, MKV, or raw .hevc/.h265 streams.
2. Pick H.264 MP4 for maximum compatibility, or the instant "hvc1" repackaging for Apple devices.
3. For H.264, choose the maximum resolution and quality; 1080p or 720p is much faster than 4K.
4. Download the MP4.

Formula

Encode time ≈ frames ÷ (frames per second this device manages)

The browser decodes HEVC in software on one processor core, then encodes H.264 with x264. Lowering the output resolution saves encoding time, but every source frame is still decoded at full size, so 4K sources stay slow. The speed actually reached is shown with the result. AAC and MP3 sound is copied; other sound is converted to AAC. The "hvc1" mode copies video and sound unchanged and only changes the container and its codec tag.

Example

A 30-second 1080p iPhone clip at 30 fps has 900 frames. Converted to 720p at about 6.5 frames per second (measured on a recent desktop), it takes roughly 2½ minutes; kept at 1080p, at about 3.7 frames per second, roughly 4 minutes. The same clip repackaged with the hvc1 tag is ready in a second or two at the same size.