Area of a sector of a circle calculator

\[ A = {\theta \over 360} \pi r^2 \] where A is the area, θ is the central angle and r is the radius of the circle.

So if we substitute the values of the angle and radius into this equation, we get: \[ A = {2 {1 \over 2} \over 2} \cdot 16^2 = {2 {1 \over 2} \over 2} \cdot 256 = 320 \]

Area of a sector Calculator is a free online tool that displays the area of the sector. BYJU’S online area of a sector calculator tool makes the calculation faster and it displays the area of a sector in a fraction of seconds.

How to Use the Area of a sector Calculator?

The procedure to use the area of a sector calculator is as follows:

Step 1: Enter the arc length and theta value in the input field

Step 2: Now click the button “Calculate” to get the area of a sector 

Step 3: Finally, the area of a sector will be displayed in the output field

What is Meant by Area of a sector?

In mathematics, the area of a sector is proportional to the arc length. It is also known as the sector area. Generally, the sector is defined as the part of a circle, which is enclosed by the two radii and the intercepted arc. In other words, the sector is the pie-shaped part of the circle. Thus, the

Additional Information
A sector (of a circle) is made by drawing two lines from the centre of the circle to the circumference, and it looks like the usual 'wedge' cut from a cake.
There are two special cases.
If the angle is 180 degrees then the sector is a semi-circle.
If the angle is 360 degrees then the sector is a full circle.
Clearly the angle cannot be greater than 360 degrees.
Where (for brevity) it says 'radius', 'arc' and so on, it should, more correctly, be something like 'length of radius' or 'arc-length' etc, and 'angle' means 'angle at the centre'.

A problem not dealt with by this calculator is where the length of the chord (c) and the height (h) between the chord and arc are known, and it is required to find the radius (r).r   =  (c² / 8h) + (h / 2)In words: c squared divided by 8h plus (h divided by 2)

If the perimeter is needed, add together the lengths of

radius + radius + arc

The formula for the area of a sector is (angle / 360) x π x radius2. The figure below illustrates the measurement:

Area of a sector of a circle calculator

As you can easily see, it is quite similar to that of a circle, but modified to account for the fact that a sector is just a part of a circle. Measuring the diameter is easier in many practical situations, so another convenient way to write the formula is (angle / 360) x π x (diameter / 2)2. The radius can be expressed as either degrees or radians, with our area of a sector calculator accepting only degrees for now (let us know if it would help you if it supported radians as well). π is, of course, the mathematical constant equal to about 3.14159.

    Area of a Sector calculation

You need to measure or know two things: the sector's radius and its angle. If the sector is a quadrant, then the angle is 90°. There are different tools for measuring angles, depending on your particular situation. A protractor can be useful in many cases.

After you have obtained the measurements, just apply the formula above or use our sector calculator as an easier and faster alternative.


    Example: find the area of a sector

As established, the only two measurements needed to calculate the area of a sector are its angle and radius. For example, if the angle is 45° and the radius 10 inches, the area is (45 / 360) x 3.14159 x 102 = 0.125 x 3.14159 x 100 = 39.27 square inches.

Calculate the area of a sector using the central angle and radius below and learn the formula and steps to solve it below.

Central Angle (θ):

Radius (r):

Diameter:

HELP

Area of a sector of a circle calculator

Results:

Sector Area

 

Arc Length (s)

 

Chord Length (a)

 

Learn how we calculated this below

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  • How to Calculate Sector Area
  • Sector Area Formula

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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.

Area of a sector of a circle calculator

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.

How do you calculate the area of a sector of a circle?

The formula for the area of the sector of a circle is 𝜃/360o (𝜋r2) where r is the radius of the circle and 𝜃 is the angle of the sector.

How do you calculate area of sector?

Sector area formula The formula for sector area is simple - multiply the central angle by the radius squared, and divide by 2: Sector Area = r² × α / 2.

How do you find the area of an arc?

A = (θ/360°) × πr2 θ is the sector angle subtended by the arcs at the center (in degrees), r is the radius of the circle. If the subtended angle θ is in radians, the area is given by, A = 1/2 × r2 × θ.