How to Convert HEVC/H.265 to H.264: Complete Guide for Windows and Mac

iPhones record in HEVC (H.265) by default since iOS 11. Modern cameras do the same. While HEVC files are 40–50% smaller at the same quality, they cause headaches: older TVs won't play them, many editors won't import them, and some sharing platforms reject them. This guide shows you how to convert HEVC to H.264 quickly on Windows and Mac.

HEVC vs. H.264: What's the Difference?

Both H.265 (HEVC) and H.264 are video codecs — algorithms that compress and decompress video data. The main differences:

| Feature | H.264 | H.265 (HEVC) | |---------|-------|--------------| | Compression efficiency | Good | 40–50% better than H.264 | | File size (same quality) | Larger | Smaller | | Encoding speed | Fast | Slower | | Compatibility | Universal | Limited (newer devices/software) | | CPU decoding support | All hardware | 2015+ hardware |

Why HEVC causes problems:

Smart TVs older than 2017–2018 often lack HEVC decoders

Windows Media Player requires a paid HEVC codec extension on Windows 10/11

Some video editors (older versions of Premiere, DaVinci Resolve on older GPUs) struggle with HEVC

Social media platforms accept HEVC but re-encode it, so H.264 uploads often process faster and more reliably

Some workplace collaboration tools (older Zoom, Teams) have limited HEVC support

Method 1: Convert with VideoConvert (Easiest, Windows & Mac)

VideoConvert converts HEVC to H.264 entirely on your device — no cloud upload, no account required.

Open VideoConvert (download at videoconvert.video)

Upload your HEVC file — .mov files from iPhone or .mp4 from cameras both work

Select MP4 as the output format

In the advanced settings panel, the output codec defaults to H.264 — leave this selected

Choose quality: High (CRF 18) for archival, Medium (CRF 23) for sharing

Click Convert and download the H.264 MP4

VideoConvert uses FFmpeg under the hood, so quality and speed match what you'd get from manual FFmpeg commands — without needing the command line.

Batch conversion: Pro users can drop multiple HEVC files and convert them all to H.264 in a single run.

Method 2: Convert with FFmpeg (Free, Any Platform)

FFmpeg is free and handles HEVC-to-H.264 conversion with a single command.

```bash ffmpeg -i input.hevc.mp4 -c:v libx264 -crf 23 -preset medium -c:a copy output.h264.mp4 ```

What these flags do:

`-c:v libx264` — use H.264 encoder

`-crf 23` — quality level (18 = high quality, 28 = smaller file)

`-preset medium` — encoding speed vs. compression tradeoff (use `fast` to speed up, `slow` for smaller files)

`-c:a copy` — copy audio without re-encoding (preserves quality, faster)

For iPhone MOV files: ```bash ffmpeg -i IMG_1234.MOV -c:v libx264 -crf 23 -preset medium -c:a aac -b:a 192k output.mp4 ```

The `-c:a aac` flag re-encodes audio in case the original audio codec isn't compatible with MP4.

Method 3: HandBrake (Free GUI, Windows & Mac)

HandBrake is a popular free transcoder with a graphical interface.

Download HandBrake from handbrake.fr

Open your HEVC file (File > Open Source)

In the Video tab, set Video Codec to `H.264 (x264)`

Set Constant Quality to RF 20–22 for high quality

Click Start Encode

HandBrake adds a watermark-free output but is slower than FFmpeg for batch jobs and doesn't have the same granular control.

What Happens to Quality During HEVC to H.264 Conversion?

HEVC-to-H.264 is a transcoding operation — the video is decoded from HEVC and re-encoded as H.264. This introduces some generation loss.

Minimizing quality loss:

Use a lower CRF value (higher quality): CRF 18 instead of CRF 23

Do not upscale the resolution during conversion

Convert at the native frame rate (don't change fps)

Avoid converting more than once — each transcode accumulates quality loss

Expected quality: Converting HEVC CRF 28 to H.264 CRF 18 typically yields a result that looks identical to the original at 2–3x the file size. If file size is a concern, CRF 23–25 gives a good balance.

File Size After Conversion

Expect H.264 files to be 30–60% larger than the equivalent HEVC file at the same quality. This is the tradeoff for better compatibility.

| Source | HEVC size | H.264 equivalent | |--------|-----------|-----------------| | 10-min 4K iPhone footage | ~1.5 GB | ~2.5–3 GB | | 5-min 1080p camera | ~600 MB | ~900 MB–1.2 GB | | 2-min screen recording | ~200 MB | ~280–350 MB |

If file size is a primary concern and compatibility is less important, consider staying with HEVC but ensuring your target platforms support it before distributing.

Fixing the iPhone HEVC Problem Permanently

If you're always converting iPhone footage, fix it at the source:

Settings > Camera > Formats

Select Most Compatible instead of High Efficiency

This records in H.264 + AAC (MOV container), which is universally compatible. You trade ~40% storage space for instant compatibility everywhere.

Alternatively, AirDrop transfers from iPhone to Mac automatically convert HEVC to H.264 when the Mac's version of macOS is older than High Sierra.

Summary: HEVC to H.264 Conversion Options

| Method | Speed | Quality | Ease | |--------|-------|---------|------| | VideoConvert | Fast | Excellent | Easiest | | FFmpeg CLI | Fastest | Excellent | Requires CLI knowledge | | HandBrake | Moderate | Good | Easy GUI |

For most users, VideoConvert provides the quickest path from HEVC to compatible H.264 with no technical knowledge required.