SweeperX
How to compress a video on iPhone without losing quality you will miss
What video actually costs per minute
Apple publishes these numbers inside the phone, at Settings → Camera → Record Video. They are worth reading once, because the gap between the options is much wider than the picture-quality gap:
| Setting | Per minute | Ten minutes |
|---|---|---|
| 720p HD, 30 fps | ~30 MB | ~0.3 GB |
| 1080p HD, 30 fps | ~65 MB | ~0.65 GB |
| 1080p HD, 60 fps | ~100 MB | ~1 GB |
| 4K, 30 fps | ~170 MB | ~1.7 GB |
| 4K, 60 fps | ~400 MB | ~4 GB |
Three minutes of 4K/60 is larger than a thousand photos. If your phone is full and you have any video on it at all, this is where to look first — before duplicates, before screenshots, before anything.
What a codec throws away
Understanding this makes the trade-off obvious rather than frightening.
A video codec saves space in two ways. First, it stores most frames as differences from the frame before rather than as complete pictures. In a clip of someone talking, the wall behind them is identical in every frame, so it is stored once. This part of compression is close to free: it exploits redundancy that carries no information.
Second, it discards fine detail your eye weights least — subtle variations in areas of similar colour, high-frequency texture in a moving scene. This part is lossy, and it is the dial that quality settings control.
Two consequences follow. Compressing a video shot at a higher resolution than you will ever watch is nearly free in perceptual terms — you are discarding detail that your screen cannot show. And re-compressing an already-compressed video repeatedly is not: each pass throws away detail relative to an already-degraded copy, and it accumulates. Compress once, from the original, to a sensible target.
The codec matters too. HEVC (H.265) achieves roughly the same visual quality as H.264 at around half the bitrate. It is the better choice for anything staying on modern Apple devices. H.264 is the choice when a file has to play somewhere old or unpredictable — a Windows machine, an older Android phone, an unfamiliar TV.
Compressing without buying anything
iOS has no built-in compressor for videos already in your library. There is no “reduce size” button in Photos. The nearest free route is Apple's own iMovie:
- Install iMovie from the App Store, if it is not already there. It is free.
- Start a new Movie project and add the clip.
- Tap Done, then the share button, then Save Video.
- Choose a smaller resolution — 720p or 540p.
This writes a new, smaller video into your library. It does not remove the original, so your storage goes up until you delete the big one yourself — and then it does not go down for 30 days unless you empty Recently Deleted, which is the single most common reason people think cleaning up did nothing.
It works, and it is fine for a handful of clips. For forty videos it is an evening of tapping, which is the entire reason bulk tools exist.
Fix the camera, not just the library
Compressing what you already shot solves today. Changing what the camera records solves the rest of the year.
In Settings → Camera → Record Video, ask yourself honestly where the video ends up. If the answer is “on my phone, and occasionally sent to someone”, 1080p at 30 fps is the right setting and it costs a sixth of 4K/60. Reserve 4K for things you know you will edit or watch on a television.
While you are there, check that Formats is set to High Efficiency rather than Most Compatible. High Efficiency records HEVC and is roughly half the size for the same footage. Compatibility is only a concern if you routinely move raw files to older non-Apple hardware — sharing through Photos, Messages or AirDrop converts on the fly when it needs to.
Finding the videos that matter
Before compressing anything, find out which four videos are the problem. Almost always it is a handful, not a spread.
The Photos app makes this harder than it should: there is no way to sort your library by file size. What you can do is narrow it. Go to Albums → Media Types → Videos to see every video in one place, and sort mentally by duration — length is a decent proxy for size when everything was shot at the same setting.
A better read comes from Settings → General → iPhone Storage. Wait for the bar chart to populate, then look at what Photos is consuming in total. That tells you whether video is your problem at all before you spend an evening on it. There is more on reading that screen properly here.
Two places videos hide that people forget: Messages, where every clip anyone ever sent you is retained by default, and the Files app under “On My iPhone”, where downloads accumulate outside your photo library entirely. Neither shows up in Photos, and neither gets compressed by anything pointed at your camera roll.
Choosing a target you will not regret
- Keep at 1080p anything with people in it that you might rewatch. It is indistinguishable from 4K on a phone and comfortable on a laptop.
- Drop to 720p for clips you are keeping for the record rather than the picture — a whiteboard, a car park level, a parcel on a doorstep.
- Leave alone anything you might edit properly later, and anything shot in low light. Dark footage is noisy, noise is expensive to compress, and re-encoding it is where compression looks worst.
- Never re-compress a compressed clip. If a video already came to you through a chat app, it has been through this once. Squeezing it again buys little and costs visibly.
If iCloud Photos is on
Two things change, and both catch people out.
First, with Optimise iPhone Storage enabled, the full-resolution original of a video may not be on your phone at all — only a smaller stand-in, with the original in iCloud. Compressing it means fetching the original back down first, which needs a connection and takes as long as the download takes. There is nothing wrong with this, but a 4 GB library of optimised video will not compress in five minutes.
Second, compressing a video and deleting the original deletes it from iCloud too, and therefore from your iPad and your Mac. That is usually what you want, and it is never what you want by accident. The full picture of what “delete” means on a synced library is worth ten minutes.
The order that protects you
Whatever tool you use, insist on this sequence:
- The new file is written and verified first.
- Only then is the original offered for removal.
- Only after you confirm does the original go to Recently Deleted, where it stays recoverable for 30 days.
Any tool that deletes the original before the replacement exists on disk is one power failure away from losing your video. It is a small detail and it is the whole ballgame.
If you want it done in bulk
The manual route is fine for a few clips and unbearable for forty. What a tool should add is not magic compression — the codecs are the same ones iMovie uses — but selection: showing you which videos are worth the effort, and what each one would become, before you commit to anything.
SweeperX does this with three profiles and a size threshold: HEVC 1080p for footage you will rewatch, 720p when you want the space more than the pixels, H.264 when a file has to play anywhere. The list shows each video's current size and its estimated result before you select it, and hides everything under a size you set so four hundred short clips do not bury the four that matter. The new file is written and checked before the original is staged, and nothing is removed until you confirm the batch. All of it runs on the phone — no upload, no cloud transcode, and nothing you cannot verify yourself.
Next: Live Photos Are Quietly Costing You Gigabytes — the video attached to photos you never think of as video.