Raio da Circunferência Inscrita

The inscribed circle radius calculator determines the radius of the circle that touches all sides of a polygon internally, typically a triangle. The formula used is r = A / s, where A is the area of the polygon and s is the semiperimeter (half the perimeter). For triangles, this formula is direct and accurate. The tool is useful for geometry students, engineers, and architects who need to calculate properties of inscribed figures.

How it works: simply enter the area and semiperimeter of the polygon. The calculator divides the area by the semiperimeter and displays the radius. For triangles, you can compute the area using base and height or Heron's formula. The semiperimeter is the sum of the sides divided by two. The tool accepts decimal numbers and provides precise results.

Use this calculator when you need the radius of the inscribed circle in geometry problems, such as in civil engineering projects (circular beam calculations), mechanical part design, or school exercises. It is especially useful for quickly verifying results without manual errors.

Cautions: ensure the polygon is tangential (all sides touch the circle). For triangles, it always works. For other polygons, verify tangency. Also, use consistent units (meters, centimeters) for area and length. The calculator does not validate input, so double-check your data.