Aspect ratio and crop calculator for Shorts, TikTok and Reels
Enter your video size and pick a format. See the exact crop area, how much of the frame you keep, and the size to export at.
Your numbers stay in this browser. Nothing is sent anywhere.
Sample footage: Mixkit
Quick answer: cropping a 1920 × 1080 (16:9) video to 9:16 leaves a 608 × 1080 slice, about 32% of the frame. Export vertical video at 1080 × 1920. Record in 4K (3840 × 2160) and the 9:16 crop is 1215 × 2160, sharp enough to export without upscaling.
Standard export sizes
| Format | Ratio | Export size |
|---|---|---|
| Shorts, TikTok, Reels | 9:16 | 1080 × 1920 |
| Instagram portrait post | 4:5 | 1080 × 1350 |
| Square post | 1:1 | 1080 × 1080 |
| YouTube video | 16:9 | 1920 × 1080 |
Crop or fit?
Crop to fill uses the whole vertical screen but cuts off the sides, so it works for one speaker in the middle of the frame. Fit with bars keeps everything in the shot but leaves empty space, which many creators fill with a title or captions. Keep text inside the safe zone either way.
Cropping many clips by hand is slow. AI video clippers reframe wide videos to 9:16 and follow the speaker automatically. Read what aspect ratio means, or check your export with the video file size calculator.
Questions
What aspect ratio are YouTube Shorts, TikTok and Reels?
All three use vertical 9:16 video, usually exported at 1080 × 1920 pixels. YouTube Help says a Short can be square or vertical; wider videos count as regular videos.
How do I turn a 16:9 video into 9:16?
Either crop a vertical slice out of the wide frame (you keep about 32% of the picture, so the subject must be near the middle) or fit the whole frame inside a vertical canvas with bars above and below. AI clipping tools crop automatically and follow the speaker.
How much of a 1920 × 1080 video is left after cropping to 9:16?
A 9:16 crop of a 1920 × 1080 frame is 608 × 1080 pixels, about 32% of the original width. Scaling that up to 1080 × 1920 makes it look softer, so record in 4K if you plan to crop.
What size should a 4:5 Instagram post be?
1080 × 1350 pixels is the standard export size for a 4:5 portrait post. The calculator shows the crop area for any source size.
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