Apple ProRes on iPhone Pro records roughly 6 GB per minute at 4K, so a five-minute clip can eat 30 GB before you blink. You enable it at Settings > Camera > Formats > Apple ProRes, and the smartest way to manage it is to shoot ProRes only when you need it and offload finished clips off the phone fast.
TL;DR
- ProRes 4K is about 6 GB/min; ProRes HD (1080p) is far smaller, roughly 1.7 GB/min.
- Enable or disable it at Settings > Camera > Formats > Apple ProRes.
- Without an external drive, an iPhone Pro caps ProRes 4K recording at 1080p; you need a connected SSD or higher-capacity model for long 4K ProRes takes.
- Offload clips to a computer or external drive, then delete the local copy to reclaim space.
- Deleting only moves files to Recently Deleted for about 30 days, so back up before you wipe anything permanently.
What is ProRes and why are the files so big?
ProRes is Apple's professional video codec built for editing, not for small file sizes. Instead of heavily compressing footage like HEVC does, it keeps far more image data per frame so colorists and editors have room to grade and cut. That quality is exactly why one minute of 4K ProRes runs around 6 GB, versus roughly 400 MB/min for ordinary 4K/60 HEVC. The math is brutal: 10 minutes of 4K ProRes is about 60 GB.
How do I turn ProRes on or off?
Go to Settings > Camera > Formats, then toggle Apple ProRes. On supported iPhone Pro models you can also choose the encoding under ProRes Encoding (for example, HEVC-based vs. the larger Apple ProRes). In the Camera app, tap the ProRes badge in the top corner to switch it on or off for a single shoot without diving into Settings. If you only record ProRes for specific projects, leave the toggle off as your default so you never fill storage by accident.
When should I actually use ProRes?
Use ProRes when you plan to color grade, do serious editing, or deliver professional footage where compression artifacts matter. For everyday clips, social posts, or family video, standard HEVC at 4K looks great and takes a fraction of the space. If you are unsure whether you need 4K at all, see how to change iPhone camera settings to save storage. And before a big shoot, it pays to free up space before recording 4K video on iPhone so you don't hit a wall mid-take.
What iOS does natively, and where it stops
Natively, iOS lets you record ProRes directly to a connected external SSD over USB-C, which is the only way to capture long 4K ProRes takes on most models because internal storage limits 4K ProRes recording on base-capacity phones. The Files app and Photos let you copy, move, and delete clips, and Photos shows you total Videos usage under Settings > General > iPhone Storage > Photos. Where iOS stops: it won't tell you which individual videos are the biggest space hogs, and it won't batch-select your largest ProRes files for you. That's tedious to do by hand when you have hundreds of clips.
How do I offload ProRes files to free space?
The reliable flow is copy-verify-delete:
- Connect the iPhone to a Mac or PC, or plug in a USB-C external drive.
- In the Files app, open On My iPhone or Photos, then drag or share the clips to the drive or computer.
- Confirm the files opened and play correctly on the destination.
- Back in Photos, delete the local copies and then empty Recently Deleted.
For a guided walk-through of moving clips, see how to move large videos off iPhone to free space and how to find and delete large videos without deleting photos. If you'd rather find every oversized ProRes clip in seconds instead of scrolling, Cleanor for iPhone sorts your library by file size so the biggest videos surface first.
What this cannot do, and the recoverability note
No tool shrinks an existing ProRes file without re-encoding it, which defeats the point of shooting ProRes in the first place. If you only want smaller files, compress videos without losing visible quality instead. And remember: deleting a video in Photos moves it to Recently Deleted for about 30 days, after which it is gone for good. Always confirm your backup or external copy plays before you empty Recently Deleted, because permanent deletion is not reversible.
FAQ
How many minutes of ProRes can my iPhone hold?
At roughly 6 GB/min for 4K, a 256 GB phone with about 100 GB free holds around 16 minutes. Recording to an external SSD removes that limit.
Does turning off ProRes delete my existing clips?
No. Toggling Apple ProRes off only changes future recordings. Your already-recorded ProRes files stay in Photos until you delete them.
Can I convert ProRes to a smaller format on the iPhone?
Not in Photos directly, but a video editing app or export to HEVC will shrink it. Expect some quality trade-off and the loss of grading headroom.
Ready to clear the biggest clips fast? Try Cleanor for iPhone to surface your largest ProRes videos, or read more ways to free up iPhone space.