Quickly determine the area and perimeter of any semicircle with our easy-to-use online calculator. Simply input the radius to get accurate results for your geometry tasks, design projects, or educational needs. Learn the essential semicircle formula and its real-world relevance.
Formula:
Semicircle Definition and Formulas
A semicircle is precisely half of a circle. To find its area and perimeter, you primarily need its radius (r) or diameter (d).
Area of a Semicircle (A):
A = (1/2) × π × r²
A= Area of the Semicircleπ(Pi) ≈ 3.14159r= Radius of the Semicircle
Perimeter of a Semicircle (P):
The perimeter includes both the curved arc (half the circumference of a circle) and the straight diameter.
P = (π × r) + (2 × r) or P = π × r + d
P= Perimeter of the Semicircleπ(Pi) ≈ 3.14159r= Radius of the Semicircled= Diameter of the Semicircle (d = 2 × r)