Why does working it out by hand drift?

Multiplying by a ratio gives a fraction, but pixels are whole numbers, so there is rounding. Resize a few times and that error piles up until the image is subtly squashed.

Why show the 16:9 padding?

Putting footage of a different ratio into a video edit leaves black bars top and bottom or left and right. Knowing the thickness in advance makes it easy to place subtitles and logos.

What is the golden ratio?

Roughly 1.618 to 1. It is held to look visually stable and gets cited often in design.

Aspect ratio calculator

Name: 화면 비율 계산기
Author: KarmoLab

Ratio-locked sizes · screen ratio list · margin calculation

화면 비율 계산기

가로·세로 비율을 유지한 채 크기를 계산합니다. 화면비 목록과 여백 계산 포함

원본 크기

가로

세로

바꿀 크기 — 한쪽만 넣으면 나머지를 채웁니다

새 가로

새 세로

약분한 비16 : 9

소수 비율1.7778 : 1

넓이2,073,600 px²

방향가로형

자주 쓰는 화면비 — 누르면 원본에 적용

가로만 정하면 세로가 따라옵니다.

Works out sizes while keeping the aspect ratio. Set one side and it fills in the other, and it lists common screen ratios and the letterbox margins.

How to use it

Enter the original width and height
Enter just one side of the new size
Read the other side and the scale

Common questions

Why does working it out by hand drift?: Multiplying by a ratio gives a fraction, but pixels are whole numbers, so there is rounding. Resize a few times and that error piles up until the image is subtly squashed.
Why show the 16:9 padding?: Putting footage of a different ratio into a video edit leaves black bars top and bottom or left and right. Knowing the thickness in advance makes it easy to place subtitles and logos.
What is the golden ratio?: Roughly 1.618 to 1. It is held to look visually stable and gets cited often in design.

Other tools

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This tool page states where what you enter goes — see the badge above. All tools · KarmoLab · Who made this · Built with AI. View source