Aspect ratio resize
Fill in any fields — the empty ones are calculated, so it works in every direction.
Formula
W₁ / H₁ = W₂ / H₂
Worked example
Given: Original width = 1,920; Original height = 1,080; New width = 1,280
Result: New height = 720
How it is calculated
1. Enter the values you know. 2. The calculator converts them to base units and applies the formula. 3. The result is shown in the unit you choose.
Frequently asked questions
How do I calculate it?
Formula: W₁ / H₁ = W₂ / H₂. Given: Original width = 1,920; Original height = 1,080; New width = 1,280. Result: New height = 720.
Is the calculator free and private?
Yes. It is free, needs no sign-up and runs in your browser — the numbers you type stay on your device.