Exceljet

Quick, clean, and to the point

Surface area of a cone

Excel formula: Surface area of a cone
Generic formula 
=PI()*r*(r+SQRT(h^2+r^2))
Summary 

To calculate the surface area of a cone, you can use the PI function together with the exponent operator (^) and the SQRT function. In the example shown, the formula in D5, copied down, is:

=1/3*PI()*B5^2*C5

The formula returns the surface area of a cone with radius given in column B and height given in column C. Units are indicated generically with "u", and the resulting area is units squared (u2).

Explanation 

In geometry, the formula for calculating the surface area of a right cone is: 

The Greek letter π ("pi") represents the ratio of the circumference of a circle to its diameter. In Excel, π is represented in a formula with the PI function, which returns the number 3.14159265358979, accurate to 15 digits:

=PI() // returns 3.14159265358979

To square a number in Excel, you can use the exponentiation operator (^):

=A1^2

To get the square root of a number, you can use the SQRT function:

=SQRT(A1)

Rewriting the formula for surface area of a cone with Excel's math operators, we get:

=PI()*B5*(B5+SQRT(C5^2+B5^2))

Following Excel's order of operations, exponentiation will occur before multiplication.

Author 
Dave Bruns

Excel Formula Training

Formulas are the key to getting things done in Excel. In this accelerated training, you'll learn how to use formulas to manipulate text, work with dates and times, lookup values with VLOOKUP and INDEX & MATCH, count and sum with criteria, dynamically rank values, and create dynamic ranges. You'll also learn how to troubleshoot, trace errors, and fix problems. Instant access. See details here.

Download 200+ Excel Shortcuts

Get over 200 Excel shortcuts for Windows and Mac in one handy PDF.