How to Convert MP4 to HEVC (H.265)

How to convert MP4 to HEVC

1. 1

   FFmpeg with software encoding

   High quality: `ffmpeg -i input.mp4 -c:v libx265 -crf 22 -c:a copy output.mp4`. CRF 22 is roughly equivalent visual quality to H.264 CRF 18. Lower CRF = better quality, larger file. For 4K: use `-preset slow` for better compression at the cost of encode time. For streaming: add `-movflags +faststart` to put the MP4 index at the start of the file. Audio is copied directly (-c:a copy) since the container doesn't change.

2. 2

   FFmpeg with hardware acceleration (NVIDIA)

   NVIDIA GPU encoding (NVENC) is 5–10× faster than CPU: `ffmpeg -i input.mp4 -c:v hevc_nvenc -rc:v vbr -cq:v 22 -c:a copy output.mp4`. Requires an NVIDIA GPU with NVENC support (GeForce GTX 950+). For quality tuning: `-cq:v` is analogous to CRF (lower = better). NVENC produces slightly larger files than libx265 at equivalent perceived quality but encodes in real-time or faster.

3. 3

   FFmpeg with Apple VideoToolbox (Mac M1/M2/M3)

   Apple Silicon hardware encoder: `ffmpeg -i input.mp4 -c:v hevc_videotoolbox -q:v 60 -c:a copy output.mp4`. On Apple Silicon, this uses the dedicated media engine and is extremely fast (often 3–10× real-time). `-q:v 60` is a rough equivalent to medium quality (0–100 scale, higher = better). For a more controlled bitrate: `-b:v 4M` for 4 Mbps. Verify availability: `ffmpeg -encoders | grep hevc`.

4. 4

   HandBrake (GUI, cross-platform)

   Open HandBrake. Select the MP4 source. In the Video tab, choose H.265 (x265) as the codec. Set RF (Constant Quality) to 22 — HandBrake's RF is equivalent to FFmpeg's CRF. Select a preset: 'Slow' gives better compression, 'Fast' encodes quicker. In the Audio tab, set to 'Auto Passthru' to copy existing audio without re-encoding. Click 'Start Encode'. HandBrake shows estimated file size and remaining time during encoding.