Video Compressor & ResizerHow to Resize a Video on iPhone (Change Resolution in Seconds)
Whether a form only accepts 720p, an app rejects your 4K upload, or you simply want a smaller file — resizing a video means changing its resolution. iOS can't do it natively for existing videos, but it takes seconds with the right tool.
What "resizing" a video means
Resolution is the pixel dimensions of each frame — 3840×2160 (4K), 1920×1080 (1080p), 1280×720 (720p). Resizing re-renders every frame at new dimensions. Fewer pixels = a smaller file, faster uploads, and compatibility with platforms that cap resolution. Aspect ratio stays the same, so nothing gets stretched or cropped.
Resize a video in 4 steps
- Install Video Compressor and Resizer — free on the App Store.
- Select your video from the Photos library.
- Choose the resolution percentage. This is the app's signature feature: instead of guessing at preset sizes, you scale by exact percentage.
- 4K → 1080p: set 50%
- 4K → 720p: set ~33%
- 1080p → 720p: set ~67%
- Any custom size in between — you decide
- Tap Compress. The resized video is saved to Photos; the original is untouched.
Resize your first video now — exact percentage control, free.
Download Free on the App StoreWhich resolution should I pick?
| Use case | Recommended resolution |
|---|---|
| Instagram feed / Stories / TikTok | 1080p |
| WhatsApp / Messages sharing | 720p–1080p |
| Email attachment | 720p |
| Website upload / forms with limits | 720p or the stated max |
| Archive to save storage | 50% of original |
Does resizing reduce quality?
Downscaling itself is a clean operation — you keep full sharpness at the new size. Quality only visibly suffers if you later blow the video back up to full screen on a much larger display. Pair the resize with a high quality level and the result looks excellent everywhere it's meant to be watched. More in compress without losing quality.