Sector Area Calculator
Calculate the area of a sector using the central angle and radius below and learn the formula and steps to solve it below.
Arc Length (s)
Chord Length (a)
On this page:
How to Calculate Sector Area
A sector is a pie-slice shaped portion of a circle surrounded by two radii edges and bounded by the circle’s outer arc.
To calculate the area of a sector, a simple formula can be used.
Sector Area Formula
The area of a sector can be found using the formula:
sector area = r² × θ / 2
Thus, a sector’s area is equal to the radius r squared times the central angle θ in radians, divided by 2.
Trying to solve the area of a segment? Try our segment area calculator.
For example, find the area of a sector with a radius of 12 and a central angle of 1.5 radians.
sector area = 12² × 1.5 / 2
sector area = 144 × 1.5 / 2
sector area = 216 / 2
sector area = 108
Thus, the area of the sector is 108.
You might also find our arc length calculator useful for solving the arc length of a sector.