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.


Sector Area


Arc Length (s)


Chord Length (a)

Learn how we calculated this below

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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.

diagram of a sector showing the radius, central angle, chord length, and arc length

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.

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