Screen Size Converter Calculator

Work out screen size converter instantly with clear inputs, formula shown and shareable results.

About Screen Size Converter Calculator

Screens are sold by diagonal, which hides how much area you actually get. Splitting the diagonal by the aspect ratio gives width and height: a 27 inch 16:9 panel is 59.8 by 33.6 cm. Aspect ratio matters enormously - a 27 inch 16:9 screen has 11% less area than a 27 inch 4:3 one.

Formulas

Width and height

width = diagonal x aw / sqrt(aw^2 + ah^2), similarly for height

Area

area = width x height

Worked example

With the default values below, Screen Size Converter Calculator returns Screen Width of 59.77. Change any input above and every figure here is recalculated in your browser.

Inputs used

Screen diagonalminimum 1 in: 27 in
Aspect ratio widthminimum 0: 16
Aspect ratio heightminimum 0: 9

Results

Screen Width: 59.77 cm
Screen Height: 33.62 cm
Diagonal In Centimetres: 68.58
Visible Screen Area: 2,009.7 cm2

Step by step

1Values used
2Width and height
3Area
4Screen Width= 59.77 cm
5Screen Height= 33.62 cm
6Diagonal In Centimetres= 68.58
7Visible Screen Area= 2,009.7 cm2

Assumptions and limits

The result is derived only from the 3 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 2 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

Why does a 4:3 screen look bigger than a 16:9 of the same size?

Because a squarer rectangle encloses more area for a given diagonal. The square is the extreme case.

Is the advertised diagonal the visible area?

Usually yes for modern panels, but older CRTs quoted tube size including the bezel-hidden margin.