Frustum Calculator

A Frustum is a three-dimensional geometric shape which resembles a cone with the top cut off.

The top and base diameters are parallel and on the centre of axis.

Frustum Calculator
Height (h)
Slope Height (s)
Top Diameter (d1)
Base Diameter (d2)
Top Radius (r1)
Base Radius (r2)
Top Surface Area (T)
Lateral Surface Area (L)
Base Surface Area (B)
Total Surface Area (A)
Volume (V)

Frustum shape Calculator: This image shows a Frustum shape with associated calculations used by the Frustum Shape Calculator

The Frustram Calculator uses the following Math Formula

Slope Height of a Frustrum Formula

s = √( (r2 - r1)2+h2)

Surface area of the top of a Frustrum Formula

T = πr12

Surface area of the base of a Frustrum Formula

B = πr22

Lateral surface area of a Frustrum Formula

L = π x (r1 + r2) x s

Total area of a Frustrum Formula

a = T + B + L

Volume of a Frustrum Formula

V = (1/3) x π x h x (r12 + r22 + (r1 * r2) )


  • h: The vertical height of the frustum
  • s: The length of the sloped side
  • d1: Diameter of the top, equal to twice the top radius
  • d2: Diameter of the base, equal to twice the base radius
  • r1: Radius of the top of the frustum, equal to half the top diameter
  • r2: Radius of the base, equal to half the base diameter
  • T: Surface area of the top in square units
  • L: The Lateral surface area in square units
  • B: Surface area of the circular base in square units
  • A: A Total surface area in square units
  • V: The volume of the frustum in cubic units

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