Arch & Circle Segment Calculator

Find the radius and curved length of an arch from its span (chord) and rise.

Estimate only — not a substitute for a licensed tradesperson, a certified engineer, or sign-off from your local building surveyor. Verify against current standards and site conditions before ordering materials or starting work.

building rules differ by state, territory and council. Results are estimates - confirm requirements with your local council or state building authority before you build.