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Math formulas and calculators

Calculate area, volume, perimeter, percentages and other mathematical quantities. Each calculator shows the formula, the intermediate steps and examples of where it can be used.

Area and volume

  • Area

    Find the area of floors, walls, roof surfaces and geometric shapes from their dimensions.

  • Volume

    Calculate the volume of containers and materials such as concrete, soil, gravel and insulation.

  • Surface area: box and sphere

    Calculate the whole surface of a closed box or sphere, for example for geometry exercises or cladding.

Lengths and angles

  • Perimeter

    Find the length around a surface for baseboards, fences, edges and measuring.

  • Pythagorean theorem

    Find a side or diagonal in a right triangle for roof surfaces and measuring.

  • Slope and degrees

    Find the slope of a roof, ramp or sloping surface in percent and degrees.

Percentages and arithmetic

  • Percentage

    Calculate discounts, price increases, material waste and percentage changes.

  • VAT

    Find a price with or without VAT at the VAT rate you enter.

  • Ratio and unit price

    Scale quantities and prices when the ratio between them is fixed.

  • Average

    Find a simple or weighted average of prices, measurements and consumption.

  • Loan payment

    Calculate a fixed loan payment from the loan amount, periodic interest rate and number of payments.