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Math & Number Tools Calculator
Geometry Calculator
Use this free Geometry Calculator to calculate geometry with a cleaner layout, instant results, formulas, examples, and helpful interpretation notes.
Choose a 2D or 3D shape and enter its dimensions. Results and calculation steps update as you type.
Dimensions
Live geometry diagram
Schematic diagram; not to scale.
Results
How it was calculated
Geometry formulas
Circle
A = πr² · P = 2πr
Rectangle
A = lw · P = 2(l + w)
Square
A = s² · P = 4s
Right triangle
A = ab/2 · c = √(a² + b²) · P = a + b + c
Triangle: three sides
p = (a + b + c)/2 · A = √[p(p−a)(p−b)(p−c)] · P = a + b + c
Triangle: base and height
A = bh/2
Trapezoid
A = (a + b)h/2
Ellipse
A = πab · P ≈ π(a+b)[1+3q/(10+√(4−3q))], q = ((a−b)/(a+b))²
Sphere
V = 4πr³/3 · S = 4πr²
Cube
V = s³ · S = 6s²
Cylinder
V = πr²h · S = 2πr(r+h)
Rectangular prism
V = lwh · S = 2(lw+lh+wh)
Cone
V = πr²h/3 · S = πr(r+√(r²+h²))
Base and height determine a triangle’s area, but not its perimeter. Use the right-triangle or three-sides mode for perimeter.
Two parallel bases and the height determine the trapezoid’s area, but not its perimeter; the other two sides are also needed.
How to use this calculator
- Enter the values requested by the Geometry Calculator.
- Use the optional fields when they match your real situation.
- Read the result, then compare it with the formula notes and examples below.
Accuracy tips
- Keep intermediate values visible when possible so you can spot typing mistakes.
- Use the examples to confirm whether the calculator expects percentages, decimals, or whole numbers.
- If the answer is used for school or work, round only after the final calculation.
Why this helps
- Designed for quick math & number tools checks with a focused input area.
- Helpful explanations are kept on the same page so the result is easier to understand.
- The page can be edited directly from the synced WordPress HTML file.
Regular hexagon formulas
For area, perimeter, side length, apothem, radius, and diagonal of a six-sided shape, use the Hexagon Calculator.
Geometry Calculator FAQ
How do I use the Geometry Calculator?
Fill in the fields in the Geometry Calculator, then press the calculate button or update the inputs to see the result.
Are the Geometry Calculator results accurate?
The result is an estimate based on the values you enter. It is useful for planning and checking, but important decisions should be verified with the original data or a qualified professional.
Can I use the Geometry Calculator on mobile?
Yes. The updated layout uses larger inputs, clearer spacing, and responsive cards so the Geometry Calculator works on phones, tablets, and desktop screens.
Why does this page include formulas and examples?
Formulas and examples make the result easier to audit, help users learn the calculation, and improve the page for search engines without relying on Elementor.
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