Geometric Computation
Circle
Radius
from Secant & Sagitta
Enter chord length and sagitta — receive the radius
Diagram
Known Values
Secant (chord) length
L
Full length of the chord inside the circle
Sagitta (gap from chord to arc)
h
Perpendicular distance from chord midpoint to the nearest arc point
Radius
—
units
Formula:
r = h/2 + L²/(8h)
How It Works