Skip to content
OneKitly
Sign up · Sign in

Aspect ratio calculator

Find the aspect ratio of any width and height, like 16:9.

Related tools

All Data & computing tools →
Megapixel calculatorCompute the megapixels of an image from its width and height in pixels.Print size calculatorFind the maximum print size of an image from its pixel dimensions and DPI.Screen size calculatorCompute a screen's width and height in cm from its diagonal and aspect ratio.ASCII Table ReferenceFull ASCII table (0-127) with a decimal / hex / octal / binary / character converter and a text-to-codes panel.Audio file size calculatorEstimate an uncompressed audio file's size from its length, sample rate and bit depth.Bandwidth CalculatorEstimate the internet speed your household needs.Bitrate CalculatorCompute the bitrate of a media file from its size and duration.Git command generatorA searchable, task-first Git cheat sheet: describe what you want to do — create a branch, undo the last commit, stash your work, squash, rebase, cherry-pick, force-push safely — and get the exact command with editable placeholders. Each is colour-coded by risk so you know which ones rewrite history or delete data.

Enter Width (px), Height (px) and the Aspect ratio calculator works out Aspect ratio, Ratio (decimal) straight away. For instance, with Width (px) = 1,920 and Height (px) = 1,080 it returns Aspect ratio = 16:9 and Ratio (decimal) = 1.778.

How to use it

  1. Enter your values: Width (px), Height (px).
  2. Read the result instantly: Aspect ratio, Ratio (decimal).

Frequently asked questions

What does the Aspect ratio calculator actually compute?

It takes Width (px) and Height (px) and derives Aspect ratio and Ratio (decimal) from them. The calculation is live as you type, so the result updates on every change.

What information do I need to provide?

2 values: Width (px) and Height (px). Nothing else is required — no account, no file upload.

Can you show a worked example?

With Width (px) = 1,920 and Height (px) = 1,080, the calculator returns Aspect ratio = 16:9 and Ratio (decimal) = 1.778. Those figures come from running this exact tool, so you can reproduce them by entering the same values.

When would I actually use this?

Finding out how big a thing will be before you make it: how many gigabytes an hour of footage takes, how long a file needs on the connection you have, how large a photo prints before it goes soft, what bitrate fits the budget you were given.

What is the most common mistake?

Reading a figure in one unit next to a figure in another. Megabits are not megabytes and the eight-fold gap sinks most transfer estimates; a kilobyte is 1 000 bytes to a drive maker and 1 024 to the operating system; pixels are not dots per inch. None of it is hard arithmetic — the unit on each side is what decides whether the answer means anything.

What is the difference between the Aspect ratio calculator and the Megapixel calculator?

This one returns Aspect ratio and Ratio (decimal); the Megapixel calculator returns Megapixels. That is the whole difference — open the one whose figure you need.

Is there a tool for the next step?

Print size calculator is the closest one after this: Find the maximum print size of an image from its pixel dimensions and DPI.

Where do the figures come from, and how current are they?

Byte prefixes follow the IEC convention where a kibibyte is 1 024 bytes and a kilobyte is 1 000 — drive makers use the second, operating systems often report the first, and a disk that shrinks on arrival is that gap and nothing else. Print sizing assumes 300 dpi unless you change it.

Further reading

All guides →
ExplainerWhat Is Aspect Ratio? 16:9, 4:3 and How to Compute ItAspect ratio is the proportion of width to height. Learn what 16:9 and 4:3 mean, how to compute a ratio from pixel dimensions, and where each ratio is used.ExplainerPrinting A4 on Letter Shrinks It to 94 %A4 and US Letter differ by 5.9 mm one way and 17.6 mm the other, so "fit to page" scales the whole document to 94 %. Ten-point type becomes 9.4, and a plan drawn to scale is wrong by six per cent.ExplainerDPI, PPI, and What Actually Controls Print SizeThe DPI figure inside an image file is a label. It changes no pixels. Printed size is pixels divided by PPI — and DPI, properly used, means something else entirely: the printer's dots.How-toHow to Find the Area of a Triangle: Base × Height and Heron's FormulaTwo reliable ways to find a triangle's area: half base times height when you know the height, and Heron's formula when you only know the three sides.ExplainerFrame Rates, Timecode, and the Drop-Frame That Drops NothingFrames = duration × rate is trivial until the rate is 29.97. Non-drop timecode then drifts exactly 3.6 seconds an hour. Drop-frame corrects it by skipping 108 frame numbers — the same 108 — but the correction is not perfect: counting every frame shows a residual of 3.6 milliseconds per hour.ExplainerHow Big Is That Audio File?Uncompressed audio size is exact arithmetic: sample rate × bit depth × channels × seconds ÷ 8. CD audio is 176,400 bytes per second. A 320 kbps MP3, by contrast, is bitrate × duration and does not depend on the sample rate at all — 2,400,000 bytes a minute whether it came from 44.1 or 48 kHz.