Geometry Calculators

Circle calculator: enter the radius to get the area, circumference and diameter in one step, with the pi formulas and working written out for you.

Rectangle calculator: enter length and width to get the area, perimeter and diagonal at once. Useful for rooms, gardens, screens and materials.

Triangle area calculator using base and height. Get the area from the half base times height formula, with each step of the working shown.

Cylinder volume calculator: enter radius and height to get the volume and total surface area, useful for tanks, pipes, cans and containers.

Sphere volume calculator: enter the radius to get the volume and surface area of a sphere, with the 4/3 pi r cubed formula worked through.

Square footage calculator: enter length and width in feet to get the area in square feet, square meters and acres for rooms, floors and land.