Area of a SemiCircle Calculator
How do you find the area of a semicircle easily? The Area of a SemiCircle Calculator is a useful tool to quickly determine the area of a semicircle based on its radius. Simply enter the radius value into the tool and it will display Area of Semi Circle.
What is the Area of a SemiCircle?
The area of a semicircle is half the area of a full circle. It’s useful in various fields such as geometry, architecture, and engineering. Calculating this area involves using the radius. The radius is the distance from the center of the circle to its edge.
How to Use the Calculator
To use the calculator, follow these steps:
 Enter the radius in the input field labeled “Radius (r)”.
 Click the “Calculate” button.
 The area will be displayed in the “Area of SemiCircle” field.
How to Calculate the Area of a SemiCircle
Formula:
$\text{Area} = \frac{1}{2} \times \pi \times r^2$
Variables:
Variable  Description 

$r$

Radius of the semicircle 
Calculation Steps:
1. First, find the radius.
Example:
$r = 5$
2. Next, square the radius.
$r^2 = 5^2 = 25$
3. Now, multiply by π (pi).
$\pi \times 25 \approx 78.54$
4. Finally, divide by 2 to get the semicircle area.
$\frac{78.54}{2} \approx 39.27$
Calculation Example
Basic Calculation  Advanced Calculation 

Radius (r): 5  Radius (r): 5 
Angle (θ): 180  Diameter (d): 10 
Area: 39.27  Angle (θ): 180 
Area: 39.27 
FAQs
Can I just use the diameter?
Yes, with the advanced mode, you can use the diameter. The calculator will adjust the calculations accordingly.
What if the angle is less than 180 degrees?
If the angle is less than 180°, the calculator will show the area of the sector formed by that angle.
Is π always equal to 3.14?
For simplicity, we use 3.14 for π, but π is an irrational number and its value is approximately 3.14159.