Canvas Size Ratio Calculator

Work out canvas size ratio instantly with clear inputs, formula shown and shareable results.

About Canvas Size Ratio Calculator

The ratio is width over height, and the simplest fraction within a denominator of twenty is found by testing each denominator for the closest numerator. Standard canvas sizes cluster around a handful of ratios, so knowing that 60 by 80 is exactly 3:4 tells you what crop a photograph will need.

Formulas

Aspect ratio

ratio = width / height

Diagonal

diagonal = sqrt(width^2 + height^2)

Worked example

With the default values below, Canvas Size Ratio Calculator returns Aspect ratio as a decimal of 0.75000. Change any input above and every figure here is recalculated in your browser.

Inputs used

Canvas widthminimum 0.1 cm: 60 cm
Canvas heightminimum 0.1 cm: 80 cm

Results

Aspect ratio as a decimal: 0.75000
Nearest simple ratio: 3:4
Canvas area: 4,800.00 cm2
Canvas diagonal: 100.00 cm

Step by step

1Values used
2Aspect ratio
3Diagonal
4Aspect ratio as a decimal= 0.75000
5Nearest simple ratio= 3:4
6Canvas area= 4,800.00 cm2
7Canvas diagonal= 100.00 cm

Assumptions and limits

The result is derived only from the 2 inputs listed above. Anything not among them is not part of the calculation.
In particular, this calculator does not take inflation, tax, fees or charges or compounding frequency into account.
Figures are rounded for display to 5 decimal places, so totals built from several rounded parts can differ slightly from the unrounded arithmetic.

How these calculators are built and tested is described on the Methodology page. If a figure looks wrong, please report it.

Frequently Asked Questions

How is the Canvas Size Ratio figure worked out?

ratio = width / height. The ratio is width over height, and the simplest fraction within a denominator of twenty is found by testing each denominator for the closest numerator.

Why does this matter?

Standard canvas sizes cluster around a handful of ratios, so knowing that 60 by 80 is exactly 3:4 tells you what crop a photograph will need.

What do I need to enter?

Enter canvas width, canvas height. The defaults shown are a realistic worked example — swap in your own figures to get a result you can use.