Geometry Calculators
◆ Shapes & MeasurementsArea, volume, distance, slope and the right-angle maths behind real building work, with the formula and the working shown every time.
Slope Calculator
Rise over run from two points, with the angle, percent grade, roof pitch, the line in three forms and a diagram drawn to scale.
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Volume Calculator
Cube, box, triangular prism, sphere, hemisphere, cylinder, capsule, cone, frustum and pyramid, with litres and both gallons.
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Cylinder Volume
Volume and capacity of a cylinder in litres, US gallons and Imperial gallons, with hollow pipe walls and part filled tanks.
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Cone Volume
Volume, slant height, lateral and total surface area, part filled depth, and capacity in litres plus US and Imperial gallons.
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Concrete Calculator
Slabs, footings, walls, columns, post holes and steps, with yards, cubic metres, 80, 60 and 40 lb bags, 25 and 20 kg bags, and a bags or ready mix verdict.
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Area Calculator
Rectangle, triangle, circle, sector, ellipse, ring, trapezoid, polygon and L-shape, each reported in square feet, square metres, acres and hectares.
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Pythagorean Theorem Calculator
Any two sides of a right triangle give the third, three sides get the converse test, and the triangle is drawn to scale with the square on each side.
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Distance Calculator
Two points on a plane, two points in 3D space, or two latitude and longitude coordinates, with the great circle distance, the bearing and a plotted diagram.
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Frustum Calculator
Work out the volume, slant height, surface area and litre or gallon capacity of any truncated cone, from a plant pot to a grain hopper.
Open calculatorNeed plain arithmetic?
Percentages, fractions, averages, ratios and scientific expressions.
Geometry calculators for classrooms, sites and workshops
The geometry calculators turn a handful of measurements into the number you actually need: how much floor to cover, how much concrete to order, how far apart two points really are. Each one draws on the standard formula and shows the substitution, so the answer can be checked rather than trusted blindly.
The area calculator handles twelve two-dimensional shapes and reports the perimeter alongside the area. The volume, cylinder and cone calculators cover the solids that come up most, and the concrete calculator converts a slab, footing or set of post holes straight into cubic yards, cubic metres and bags.
For the maths of angles and position, the Pythagorean theorem calculator solves any missing side of a right triangle, the slope calculator reports gradient, angle and rise over run, and the distance calculator works on a plane, in 3D space or across the surface of the Earth.
Frequently Asked Questions
Are these geometry calculators free to use?
Yes. Every geometry calculator here is 100% free, with no sign-up and no limits, and each one runs entirely in your browser.
Which units do the geometry calculators use?
Most of them are unit-agnostic, so if you enter metres the answer is in metres and if you enter feet the answer is in feet. The area, volume and concrete calculators also convert the result into the common trade units for you.
Do they show the formula behind the answer?
Yes. Each page states the formula it applied and prints the substitution, so you can follow the working or reproduce it by hand.
Is my data stored anywhere?
No. Everything is calculated locally in your browser, and nothing you type is uploaded, stored or shared.