How to Compress iPhone Videos (HEVC, 4K & .MOV)

An iPhone video is usually two problems at once: it is enormous, and it is a HEVC track inside a .MOV container that a lot of software refuses to open. Compressing it with SqueezeVid solves both in one pass — drop the file into the browser compressor and you get back an H.264 MP4 that is typically 60–80% smaller and plays on Windows, Android, Discord, and every web player. Nothing is uploaded; your iPhone footage is decoded and re-encoded inside your own browser.

Why iPhone videos are so large

Your iPhone records at a very high bitrate by default, and it records more pixels than most people ever watch. These are the approximate per-minute sizes iOS itself shows under Settings → Camera → Record Video, in High Efficiency mode:

Recording setting	Approx. size per minute	10 minutes of footage
720p HD at 30 fps	~30 MB	~300 MB
1080p HD at 30 fps	~65 MB	~650 MB
1080p HD at 60 fps	~100 MB	~1 GB
4K at 30 fps	~170 MB	~1.7 GB
4K at 60 fps	~400 MB	~4 GB
ProRes 4K at 30 fps (Pro models)	~6 GB	~60 GB

That last row is not a typo. ProRes is an editing format that barely compresses at all, on purpose. If your iPhone clips are unexpectedly gigantic, check whether ProRes is switched on before you blame anything else.

The second problem: HEVC and .MOV

Since iOS 11, iPhones record in High Efficiency mode by default, which means the video track is HEVC (also called H.265) wrapped in Apple's QuickTime .MOV container. HEVC really is more efficient — roughly half the size of H.264 for the same quality — which is exactly why Apple chose it. The cost is compatibility:

• Windows does not ship HEVC playback by default; users are pushed to install a codec extension from the Microsoft Store before the file will open.
• Older Android phones and older smart TVs may decode it slowly or not at all.
• Web browsers and upload forms are far happier with H.264 MP4. A .MOV often gets rejected outright or refuses to preview inline.
• Older editing software either cannot import HEVC or stutters badly on the timeline.

H.264 in an MP4 container is still the only format you can send to a stranger and be confident it will open. That is what SqueezeVid outputs: H.264 video, AAC audio, MP4 container, with the metadata moved to the front of the file so it starts playing before it has fully downloaded.

How to compress an iPhone video

1. Get the file onto your computer — AirDrop, a cable, or iCloud. See the note below about which of those preserves HEVC.
2. Open the video compressor and drop the .MOV in. Files up to about 2GB are processed entirely in your browser; for anything larger use the large video compressor.
3. Drop 4K to 1080p if the video was shot in 4K. This is by far the biggest single saving — usually 60–75% on its own — and on a phone or a laptop screen the difference is invisible.
4. Leave the quality setting alone, or nudge it up. SqueezeVid picks a starting value based on how efficiently your source is already encoded. Around 24–26 is the sweet spot; higher means smaller.
5. Compress and download. You get an MP4. Check the before/after preview if you want to confirm quality before saving.

Realistic results

iPhone source	Settings	Typical result
4K/60 HEVC, 3 minutes, ~1.2 GB	1080p, quality 24	~150–250 MB (−80%)
4K/30 HEVC, 10 minutes, ~1.7 GB	1080p, quality 26	~250–400 MB (−75–85%)
1080p/30 HEVC, 5 minutes, ~325 MB	1080p, quality 26	~80–150 MB (−55–75%)

Note that HEVC is already an efficient codec, so converting to H.264 at the same resolution and visual quality buys you less than converting from an old, bloated format would. The saving comes mostly from the resolution drop and the quality setting — the format change is what buys you compatibility.

Two things to watch out for

HDR footage can look flat after conversion

iPhone 12 and later record HDR (Dolby Vision) by default. HDR video carries colour information that standard H.264 playback does not understand, so a straight conversion can come out looking washed out, dull, or oddly dark — this is a known effect of moving HDR footage into an SDR format, not a fault in the compression. If the colours matter to you, turn off Settings → Camera → Record Video → HDR Video before you shoot, and the problem disappears at the source.

4K HEVC is heavy work for a browser

Decoding HEVC in software is genuinely CPU-intensive, and a long 4K clip will make a laptop fan spin. It works, but be patient with it. Compressing directly on the iPhone in Safari works for short clips; a browser tab on iOS has a much tighter memory ceiling than a desktop, so a multi-gigabyte 4K file is better handled on a computer, or through the server-side path for files over 2GB.

How to stop it happening again

• Settings → Camera → Formats → Most Compatible. Your iPhone records H.264 instead of HEVC. Files get bigger, but they open everywhere without conversion. Choose this if you constantly send video to other people.
• Settings → Camera → Record Video → 1080p at 30 fps. Unless you are actually going to edit or watch on a 4K screen, this cuts your recordings by roughly two thirds and nobody will notice.
• Settings → Photos → Transfer to Mac or PC → Automatic. iOS converts HEVC to H.264 as it transfers. Choosing Keep Originals instead sends the untouched HEVC file, which is what you want if you are going to compress it yourself anyway.

Frequently asked questions

How do I convert an iPhone .MOV to MP4?

Drop the .MOV into the SqueezeVid compressor — the output is always an H.264 MP4, so compressing and converting happen in the same pass. If you only want the format change without shrinking the file much, use a low quality number and keep the original resolution. There is also a dedicated MOV to MP4 converter.

Why won't my iPhone video play on Windows?

Because it is HEVC, which Windows does not decode out of the box — you are usually prompted to buy a codec extension. Re-encoding the file to H.264 MP4 removes the dependency entirely, and the recipient does not have to install anything.

Will compressing my iPhone video ruin the quality?

Not visibly, at sensible settings. Keeping 1080p at a quality value of 24–26 produces a file most people cannot tell apart from the original on a phone or laptop screen, at a fraction of the size. The visible losses come from aggressive size targets on long clips, not from the conversion itself.

Can I compress an iPhone video on the iPhone itself?

Yes — open the compressor in Safari and pick the video from your library. It runs in the browser like it does on a desktop. Short clips are fine; very large 4K recordings can exhaust the memory a mobile browser tab is allowed, so those are more reliable on a computer.

Does my video get uploaded anywhere?

No, not for files up to about 2GB. The compression runs inside your browser with WebAssembly, so your camera roll stays on your device. Files between 2GB and 10GB can use optional server-side processing, which does upload and deletes the file automatically after processing.