A 4K iPhone video 5 min is usually 2-3 GB — too big for WhatsApp, email, or slow upload. This guide shows 10 ways to shrink from light (10%) to extreme (95%).
1. CRF 28 (default) — 60-75% smaller
CRF (Constant Rate Factor): higher = smaller. CRF 22 = high quality, 28 = balanced (default), 32 = smallest. Use Compress video Balanced preset.
2. Resize to 1080p / 720p — 50% smaller
4K → 1080p saves 70%. Use Max resolution dropdown.
3. Switch to H.265 — 50% extra
H.265 is 50% more efficient than H.264 at same quality. Use for storage; H.264 for sharing (compatibility).
4. Trim unused parts
Cut 1-2 min intro/silence with Trim tool. Combo with CRF 28 = 90% reduction.
5. Lower frame rate 60 → 30 fps
Saves 30% bitrate. Eyes barely notice.
6. Audio bitrate 320k → 128k
Audio is ~10-20% of file. Drop saves 5-10%.
7. Speed up video 1.5×-2×
Tutorial 5 min → 2.5 min. Use Speed tool.
8. Convert to GIF (short clips)
Clips < 5s smaller as GIF. Use Video → GIF.
9. Extract audio only
If only need audio, extract MP3 = 95% reduction.
10. Combo for slideshow
Compress source images first via Compress image, output 1080p, then CRF 28.
Quick decision table
| Use case | Method | Reduction |
|---|---|---|
| WhatsApp (<100 MB) | CRF 28 + 1080p | 70% |
| Email (<25 MB) | CRF 32 + 720p + trim | 95% |
| Personal storage | CRF 22 + H.265 | 40% |
| YouTube upload | CRF 22 + 1080p H.264 | 30% |