Aspect Ratio Calculator for Video
Every pixel size you need for TikTok, Reels, Shorts, YouTube and other platforms, with the safe zones marked, plus resize math and a crop-or-extend calculator for changing a video’s shape.
Free, no sign-up.
1. Pixel size and safe zone per platform
- Size
- 1080×1920 px
- Aspect ratio
- 9:16
- Safe area
- 896×1402 px
- Keep clear (T / R / B / L)
- 134 / 130 / 384 / 54 px
Right side holds like, comment, share and the profile picture; the bottom fifth holds the caption, sound and username.
Safe zones are rounded-up approximations: overlays shift a little between phones and app versions.
2. Aspect ratio and resize calculator
Ratio 16:9
Decimal 1.778
Same ratio at new width 1280×720
3. Reframe: crop or extend?
Crop
31.6%
of the picture survives; 68.4% of the width is cut away.
AI reframe (outpaint)
100%
of the picture stays; the AI paints the missing 68.4% of the new frame (above and below).
Reframe without cutting anything out
Viralance Reframe extends your clip to 9:16, 16:9, 1:1 or 4:3 with AI, so the subject stays in frame. How it works
How to size a video for every platform
- 01
Pick the platform
Choose where the video goes. You get the pixel size, the ratio and the area to keep clear of the app’s buttons and captions.
- 02
Check the safe zone
Keep text, faces and logos inside the dashed box. Everything outside can sit under the app’s overlays on some phones.
- 03
Do the resize math
Enter any width and height to get the ratio, then a new width to get the matching height in even pixels.
- 04
Plan the reframe
Pick your video’s ratio and the one you need to see how much a crop would cut, or extend the frame with AI Reframe instead.
Video sizes by platform
Recommended upload sizes. Bigger files at the same ratio are fine; the apps downscale them.
| Platform | Placement | Pixels | Ratio |
|---|---|---|---|
| TikTok | Feed video | 1080×1920 | 9:16 |
| Reels | 1080×1920 | 9:16 | |
| YouTube | Shorts | 1080×1920 | 9:16 |
| Instagram / Facebook | Stories | 1080×1920 | 9:16 |
| Feed post (portrait) | 1080×1350 | 4:5 | |
| Instagram / Facebook / LinkedIn | Square post | 1080×1080 | 1:1 |
| YouTube | Video (landscape) | 1920×1080 | 16:9 |
| X (Twitter) | Video in post | 1280×720 | 16:9 |
| Feed video | 1080×1350 | 4:5 | |
| Standard pin | 1000×1500 | 2:3 |
One video, every format
Shoot or generate for the format that matters most, usually 9:16, and keep the subject near the center. That way a 4:5 feed crop or a 1:1 square still works without re-editing.
When a crop would cut off too much, extend the frame instead. Viralance Reframe outpaints a clip to 9:16, 16:9, 1:1 or 4:3, and AI video models such as VEO 3.1 generate natively in vertical or horizontal.
Frequently asked questions
What size is a TikTok, Reels or Shorts video?
1080×1920 pixels, a 9:16 vertical frame, for all three. They accept other sizes, but 9:16 fills the whole phone screen.
What is the safe zone on TikTok?
The part of the frame not covered by the app’s interface. On TikTok the right edge holds the like, comment and share buttons and the bottom fifth holds the caption and username, so keep text and faces roughly inside the middle area the calculator marks. The numbers are rounded-up approximations, since overlays shift between devices.
How do I calculate an aspect ratio?
Divide width and height by their greatest common divisor: 1920×1080 becomes 16:9 because both divide by 120. To resize at the same ratio, new height = new width × height ÷ width, rounded to an even number for video.
How do I turn a 16:9 video into 9:16?
You can crop it, which keeps only about 32% of the width, or extend it. AI reframing (outpainting) keeps the full original picture and generates the missing area above and below, so nothing important is cut off.
Is 4:5 or 9:16 better for Instagram?
Reels are 9:16. For feed posts, 4:5 (1080×1350) takes the most height in the feed. A 9:16 video posted to the feed is shown cropped to 4:5 there, so keep the important part in the middle.
Does this tool upload my video?
No. It is a calculator that runs in your browser and uses no files. Reframing an actual video happens in the Viralance editor after you sign up.
More free tools
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- Caption & Hashtag GeneratorThree captions plus a mix of broad, niche and specific hashtags.
- AI Video Prompt GeneratorTurn a rough idea into a prompt written for VEO, Kling, Seedance or Hailuo.
- Virality PredictorAn AI read on your hook, retention risks and edits before you post.