What ratio is that? Answered.
Turn any width and height into a ratio, or get exact pixels for 16:9, 9:16, 1:1, and more. No upload.
Pure math in your browser tab. No upload, no waiting.
Whole-pixel answers for 16:9, 9:16, 1:1, 4:5, and any custom ratio.
Find a ratio, solve a missing side, or scale to fit a max size.
Need the right size and the right shape?
This tool does the math. Cutsio's resizer and reframe tools apply it to real footage — right in your browser.
Common questions.
How do I calculate aspect ratio from pixels?
Enter the width and height in the Find ratio tab. The tool divides both by their greatest common divisor — 1920×1080 becomes 16:9 — and shows the decimal value plus the closest standard ratio.
How do I find the height for a 16:9 video?
Pick the 16:9 preset in the Find pixels tab and type your width. A 1920 px wide video needs 1080 px of height; a 3840 px wide one needs 2160 px. It works for any ratio, including portrait 9:16.
What are the standard aspect ratios for video?
16:9 for YouTube and landscape, 9:16 for Shorts, Reels, and TikTok, 1:1 for square posts, 4:5 for Instagram portrait, and 21:9 for ultrawide. All are one click in the preset row.
How do I resize while keeping the aspect ratio?
Use the Scale to fit tab: enter your source size and the maximum bounds. You get the largest whole-pixel dimensions that fit without stretching — and it never upscales.
Is my data uploaded anywhere?
No. The entire calculation runs in your browser tab. Nothing is sent to a server.