Keep 4K or Drop to 1080p? Choosing Compression Settings on iPhone
Published October 19, 2026.
Your iPhone records 4K, your storage is full, and you want smaller videos you won't regret later. The biggest choice is whether the compressed video stays at 4K or drops to 1080p: a 4K frame has four times the pixels of a 1080p frame and needs a much higher bitrate to look the same.
Apple puts it plainly: faster frame rates and higher resolutions result in larger video files. This guide shows what HEVCut's presets do with resolution, frame rate, and bitrate, how to estimate the result before you compress, and when each choice makes sense.
Quick answer
- HEVCut caps videos at 1080p by default. Gentle, Standard, and High scale anything larger down to 1080p, and Maximum goes to 720p.
- To keep 4K, turn on Keep original resolution. It's a free toggle in Video Compression settings and works with every preset.
- Keep 4K for videos you'll watch on a large TV, crop or edit later, or archive as the only copy of an important day.
- Drop to 1080p for videos you watch on your phone and share in messages, and when space matters more than detail.
- Estimate the size first: bitrate in Mbps × seconds ÷ 8 = megabytes.
Change the setting
- 01
Open HEVCut and tap Compress on Home.
- 02
Tap the gear (Settings) in the toolbar and choose Video Compression.
- 03
Pick a preset: Gentle, Standard, High, or Max. The rows below it show the quality, resolution, and frame rate you'll get.
- 04
To keep 4K videos at 4K, turn on Keep original resolution. The Resolution row changes to Original.
- 05
Close the sheet. The size estimates in the list update, and the setting applies to all videos.
- 06
Compress two or three typical clips, compare them with the originals, then run the rest.
What each preset does
Each preset sets a reference bitrate for a 1080p video at 30 fps, a resolution cap, and a frame-rate cap. The sheet also shows a plain-language quality summary for each preset.
| Preset | Quality summary in the app | Reference bitrate (1080p30) | Resolution cap | Frame-rate cap |
|---|---|---|---|---|
| Gentle | Best quality | 7.5 Mbps | 1080p | Original |
| Standard (default) | Similar look | 4.5 Mbps | 1080p | 60 fps |
| High | Slightly softer | 3 Mbps | 1080p | 60 fps |
| Maximum (Max) | Noticeably softer | 1.5 Mbps | 720p | 30 fps |
With Keep original resolution on, the resolution cap becomes Original for every preset. The frame-rate cap and bitrate still follow the preset.
The bitrate adapts to resolution and frame rate
The reference bitrate is for 1080p at 30 fps. HEVCut scales it with the number of pixels per second in the output, so a 1080p60 video gets twice the reference and a 4K30 video gets four times. Two limits apply: the rate never goes above four times the reference, which is exactly 4K30, and never below about a fifth of it, so very small videos still get a watchable rate.
Here is what that means for the target video bitrate:
| Preset | 1080p30 source | 4K60 source, default (output 1080p60) | 4K30 or 4K60 source, Keep original resolution on |
|---|---|---|---|
| Gentle | 7.5 Mbps | 15 Mbps | 30 Mbps |
| Standard | 4.5 Mbps | 9 Mbps | 18 Mbps |
| High | 3 Mbps | 6 Mbps | 12 Mbps |
| Max | 0.67 Mbps (720p30) | 0.67 Mbps (720p30) | 6 Mbps (4K30) |
Because of the ceiling, a 4K60 video with Keep original resolution on gets the same budget as a 4K30 one, spread over twice as many frames.
Work out the size before you compress
Bitrate is measured in megabits per second, and there are 8 bits in a byte, so:
Size in MB ≈ video bitrate in Mbps × length in seconds ÷ 8
For a 10-minute (600-second) clip:
| Output | Target bitrate | Video size, 10 minutes |
|---|---|---|
| Standard, 1080p30 | 4.5 Mbps | about 340 MB |
| Standard, 1080p60 | 9 Mbps | about 675 MB |
| Standard, 4K kept | 18 Mbps | about 1.35 GB |
| High, 4K kept | 12 Mbps | about 900 MB |
| Gentle, 4K kept | 30 Mbps | about 2.25 GB |
| Max, 720p30 | 0.67 Mbps | about 50 MB |
Add audio on top. HEVCut re-encodes ordinary audio as AAC at 160 kbps for stereo, which is about 12 MB per 10 minutes. Spatial Audio is passed through as it was recorded.
You can run the formula backwards to see what you're starting from: a one-minute clip that takes 400 MB averages about 400 × 8 ÷ 60 ≈ 53 Mbps. Compare that with the targets above to see how much each choice can save.
Treat the result as an estimate. The encoder aims at the average bitrate rather than hitting it exactly. In our own test, a 4.5 Mbps target produced files at 4.75 to 5.49 Mbps once encoder variation, audio, and container overhead were counted.
HEVCut only offers videos it estimates will shrink by at least 5% with your current settings. If an output still comes out larger than the original, HEVCut discards it and keeps the original. A video already recorded at a low bitrate may simply not be offered.
What our test measured, and its limits
We ran HEVCut's real encoder on two short 1080p, roughly 60 fps HDR (HLG) clips of 7.6 and 5.6 seconds. This was a small exploratory test on a Mac, not an iPhone, and two clips can't stand in for your library. Treat the numbers as examples.
- Standard saved 24.7% on one clip and 66.1% on the other. The same setting can save very different amounts depending on the source.
- High saved 47.7% and 76.2%. Larger savings, with lower measured detail on both clips.
- Gentle made the first clip 19.9% larger. A bitrate target alone can't guarantee a smaller file, which is why HEVCut keeps the original when that happens.
- 60 fps versus 30 fps at the same budget: with both set to 4.5 Mbps, the 60 fps files were only 4.0% and 4.7% larger than the 30 fps files. The 30 fps versions scored about 5 points better on a still-frame detail measure, but they have half the frames, and a still-frame score can't tell you how smooth motion looks.
The practical reading: at a fixed bitrate, file size follows the bitrate, not the frame rate. HEVCut's presets give 60 fps video twice the bitrate of 30 fps to keep each frame's quality, which is why a 1080p60 result is about twice the size of a 1080p30 one. If you'd rather spend fewer bits on smoothness, Fine-tune can cap the frame rate at 30 fps or set an exact bitrate.
Try your own clips: HEVCut shows the estimated savings for each video before you compress, and lets you revert any result.
When to keep 4K
- You watch on a big screen. A large TV or projector shows the extra detail.
- You'll crop, reframe, or stabilize later. Cropping into a 4K frame can still leave a full 1080p picture. Cropping into a 1080p frame can't.
- It's an archive. Weddings, births, and once-in-a-lifetime trips are worth the extra space, especially if this compressed file becomes the only copy.
- It's drone or action-camera footage you plan to edit. See DJI HDR (HLG) on iPhone for HDR-specific choices.
With Keep original resolution on, Gentle or Standard are the natural presets. High and Max save more by giving each pixel fewer bits, which works against the reason you kept 4K.
When 1080p is enough
- You mostly watch on your phone. A phone screen is small, so the extra detail of 4K counts for less.
- The clip is mostly for sending. For a video you share in a chat, 1080p is usually plenty.
- It's an everyday clip. Kids' practice, a quick pet video, a reminder of where you parked.
- You need space now. Dropping a 4K30 video to 1080p30 at Standard targets a quarter of the bitrate of keeping it at 4K.
Frame rate and HDR
Standard and High keep up to 60 fps, so 60 fps videos stay at 60 fps. Gentle keeps the original frame rate. Max caps at 30 fps along with 720p.
HDR videos stay HDR (HLG or HDR10) in 10-bit HEVC. Dolby Vision's extra dynamic metadata isn't carried over.
Fine-tune (Pro)
If no preset fits, Fine-tune at the bottom of the sheet opens three sliders:
- Bitrate: 1 to 30 Mbps in 0.5 steps. Once you move it, it becomes an exact output bitrate whatever the resolution or frame rate.
- Resolution: Original, 4K, 1440p, 1080p, 720p, 540p, 480p, or 360p. 1440p is a middle ground between 4K and 1080p.
- Frame rate: Original, up to 60 FPS, or up to 30 FPS.
Mixing 4K and 1080p in one library
The setting applies to every video, and any video that would still shrink by at least 5% at the current setting can come up again. If you compress some clips at 4K and then switch back to 1080p, those 4K results can be offered for another pass. Two ways to keep them as they are:
- Open a video and tap Keep to leave it out of future runs.
- Filter the list by album or date before you tap Compress, so a run only covers the clips you mean.
If a video's details say it won't shrink further at the current setting, Increase compression opens the settings sheet so you can try a stronger preset for it.
Compressing hundreds of clips takes time. On iOS 26, HEVCut keeps going after you leave the app; see How to compress iPhone videos in the background.
Frequently asked questions
Does HEVCut keep 4K by default?
No. The default preset, Standard, scales videos larger than 1080p down to 1080p, and Maximum goes to 720p. Turn on Keep original resolution in Video Compression settings to keep 4K videos at 4K with any preset.
Is Keep original resolution a Pro feature?
No, it's free. Fine-tune, which lets you set an exact bitrate, a specific resolution cap, and a frame-rate cap, needs Pro.
How do I estimate the size of a compressed video?
Multiply the video bitrate in megabits per second by the length in seconds, then divide by 8 to get megabytes. Ten minutes at 4.5 Mbps is 4.5 × 600 ÷ 8, about 340 MB, plus roughly 12 MB for stereo audio. Real files land a little above or below, because the encoder treats the bitrate as a target.
Will my 60 fps videos become 30 fps?
Only with the Maximum preset, or if you choose a 30 FPS cap in Fine-tune. Standard and High keep up to 60 fps, and Gentle keeps the original frame rate.
What if 1080p looks worse than I expected?
Tap Revert on that video. HEVCut saves each compressed video as a new item and leaves the original in place until you choose Keep Compressed or delete the originals, and deleted originals stay in Recently Deleted for 30 days.