How to make videos
smaller on iPhone.

Videos you already have

Long 4K clips are the largest files on most iPhones. Compressing re-encodes them at a lower bitrate; at a gentle level the change is hard to see on a phone screen.

Step 1 of 6On the Clean tab, the Videos card shows what your videos take: 27.4 GB. Tap it.

Step 2 of 6The largest videos come first, each with its size. Tap the ones to compress.

Step 3 of 6Three picked, 19.7 GB in all: compressing them saves about 9.85 GB. Tap Compress Selected.

Step 4 of 6At Medium, 19.7 GB becomes about 9.85 GB. With Keep originals off, each original is replaced by its smaller version. Tap Compress 3 videos.

Step 5 of 6It compresses on your iPhone. Nothing is replaced until every video is ready; then iOS asks you to confirm once.

Step 6 of 63 videos compressed: the library is 9.85 GB smaller. The originals wait in Recently Deleted, and the space comes back when you empty it, or after 30 days.

Videos you record from now on

1. Open Settings › Camera › Formats and choose High Efficiency.
2. Open Settings › Camera › Record Video.
3. Pick 1080p at 30 fps for everyday clips; keep 4K for moments you'll edit or show on a big screen.

Videos stored in iCloud

With Optimize iPhone Storage on, full-size originals live in iCloud. To compress them, the iPhone downloads each original first — on Wi-Fi this is much faster.