Aspect ratio: fit, fill or stretch?
The aspect ratio is the shape of the picture — width divided by height. YouTube uses 16:9, TikTok, Reels and Shorts use 9:16, the Instagram feed prefers 4:5 or 1:1. When you move a video to a different shape, the picture and the frame no longer match, so something has to give.
Fit keeps the entire picture and fills the gaps — a blurred background looks most natural. Fill scales the video until the frame is covered and crops the edges; drag the preview to choose what stays visible. Stretch forces the picture into the new shape and distorts it, so use it only for small changes.
The resolution setting refers to the short side: 1080 turns 9:16 into 1080 × 1920 and 16:9 into 1920 × 1080 — the sizes platforms recommend.
Aspect ratios at 1080
| Ratio | Size | Used for |
|---|---|---|
| 16:9 | 1920 × 1080 | YouTube, TV, presentations |
| 9:16 | 1080 × 1920 | TikTok, Reels, Shorts, Stories |
| 1:1 | 1080 × 1080 | Instagram & Facebook feed |
| 4:5 | 1080 × 1350 | Instagram feed (tallest allowed) |
| 4:3 | 1440 × 1080 | Classic TV, iPad |
| 21:9 | 2520 × 1080 | Cinematic widescreen |
Tips
- For text and captions on vertical videos, try the TikTok / Reels / Shorts Converter.
- Need exact platform sizes for several networks at once? Use the Social Video Resizer.
- To cut away part of the picture precisely, use the Video Cropper.
- Double-click the preview to centre the video again.