Simplify a ratio, or scale dimensions to match one
An aspect ratio calculator reduces a width and height down to its simplest ratio — like turning 1920×1080 into 16:9 — and can scale a different size to match that same proportion.
Enter a width and height.
The simplified ratio appears instantly.
Optionally fill in a new width or height to scale to that ratio.
Yes — there's no paywall, no watermark, and no sign-up required.
Width and height are reduced by their greatest common divisor, the same way you'd simplify a fraction — 1920×1080 and 3840×2160 both simplify down to 16:9, for example, since they share the same proportions.
Fill in either "New width" or "New height" and the other fills in automatically to keep the same ratio as your original dimensions — useful for resizing an image or video frame without distorting it.
Yes. The ratio is just math between two numbers, so it works the same regardless of unit — type inches, centimeters, or pixels, whichever your width and height are actually measured in.
No — there's no image upload here. Enter the width and height numbers directly, whether you already know them or check them from your image editor or file properties first.
This calculates the mathematically exact simplified ratio for whatever numbers you enter. If your dimensions are slightly off from a standard ratio — common with cropped photos or odd export sizes — the result won't snap to the nearest clean ratio like 16:9 or 4:3, it'll show the real, sometimes odd-looking one.
No. Tire aspect ratio is a completely different calculation — sidewall height as a percentage of tire width, read from a size code like 205/55R16. This tool is for image, video, and screen dimension ratios, not tires.
No — everything happens in your browser. Nothing you enter is ever uploaded or sent anywhere.
Useful any time something needs to be resized without warping — a photo, a video frame, or a layout.
Find the matching height for a target width without stretching a photo.
Confirm a resolution matches the ratio you're editing in.
Scale a design to a new physical size while keeping proportions intact.
Yes — there's no paywall, no watermark, and no sign-up required.
Yes. The ratio is just math between two numbers, so it works the same regardless of unit — type inches, centimeters, or pixels, whichever your width and height are measured in.
No, there's no image upload — enter the width and height numbers directly.
This calculates the mathematically exact simplified ratio for the numbers you enter. If your dimensions are slightly off from a standard ratio — common with cropped photos or odd export sizes — the result won't snap to the nearest clean ratio, it'll show the real one.
No. Tire aspect ratio is a completely different calculation — sidewall height as a percentage of tire width, from a tire size code like 205/55R16. This tool is for image, video, and screen dimension ratios.
No. Everything happens in your browser — nothing you enter is ever uploaded or sent anywhere.