# Rectangle

To the mobile version
 Side a a = cm (centimeter) m (meter) in [int.] (inch, international) ft [int.] (foot, international) Side b b = cm (centimeter) m (meter) in [int.] (inch, international) ft [int.] (foot, international) Diagonal d = cm (centimeter) m (meter) in [int.] (inch, international) ft [int.] (foot, international) Perimeter u = cm (centimeter) m (meter) in [int.] (inch, international) ft [int.] (foot, international) Area F = cm² (square centimeter) m² (square meter) in² [int.] (square inch, international) ft² [int.] (square foot, international) Side ratio a/b =

Rounding: significant digits.
Decimal sign:

You can calculate the quantities of a rectangle (side lengths, diagonal, perimeter, area and side ratio) when you know two of them. The results are given in the units centimeter, meter, inch and foot.

Usage: Always choose the correct unit in the corresponding pull-down-menu before you type a value. Type two known quantities of a rectangle into the corresponding field After a mouse click on any free space of the window or the "calculate"-button the calculation is performed. The fields with the input quantities have a light green background, the background of the output quantities are colored pink. By the help of the pull-down menus you can show the results in other units.
For a further calculation with a value that has been calculated before, click on the radio button in front of the value. The lines with this quantity will be recolored light green and become input values for the next calculation. The calculation is always performed with the two quantities changed last.
Click on the "reset"-button to reset the calculation.

Example: Your desktop computer has a rectangular screen with a side ratio of 16:9 and a diagonal of 26 inch. You want to calculate what diagonal length a screen with the same area and a side ration of 4:3 would have.
For the side ratio type "16/9" into the corresponding field. After the next mouse click this input is changed to the decimal value (1.7778) For the diagonal choose "inch" as unit and type "26" into the corresponding field. After a mouse click on any free space of the window or the "calculate"-button you can read the quantitues of the rectangle of this screen (e.g. area = 0.18636 m²).
Now click on the radio button in front of the line for area in order to use this value for the next calculation. Type "4/3" into the field for the side ratio. After another mouse click on any free space of the window or the "calculate"-button you can read, that with this side ratio a diagonal of 24.53 inch would be sufficient to get the same area.

Remarks: