Floor Area Calculator

Use KALK.PRO's floor area calculator to find the square footage of your home's floor surface based on known length and width. Floor area calculator - easy and free!

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How to calculate floor area?

The floor is the bottom surface of the room and serves as the base for all the elements on it. KALK.PRO's floor area calculator will help you quickly estimate the total floor area of a room by knowing the length and width of the room. The tool can only be used for square and rectangular shaped rooms, if you have a non-standard room, scroll just below.


Floor area calculation formulas

  • Square floor area formula: S = a2, where а – side.
  • Rectangular floor area formula: S = a × b, where а, b – sides.
  • Triangular floor area formula: S = (a × h) / 2, where а – base, h – height.

If you want to calculate the floor area of an irregularly shaped room, you should divide it into simple shapes, perform the calculation using the above formulas and add up the values.

Floor area for a non-standard shaped room
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