Calculate the focal length of a spherical mirror from its radius of curvature. Works for both concave and convex mirrors with appropriate sign conventions.
Enter your values below
Positive for concave mirrors, negative for convex.
Determines the sign convention for focal length.
How this calculator works
For a spherical mirror, the focal length f is exactly half the radius of curvature R. Concave mirrors have positive f; convex mirrors have negative f.
Common questions about this calculator
These calculators are for educational and informational purposes only. While we strive for accuracy, results should be verified for critical applications. Always consult authoritative sources for engineering or scientific work.
