This page is tuned for clean geometry checks during drafting or homework around sagitta.
Informational calculator only. Verify important outputs independently before legal, tax, medical, engineering, safety-critical, contractual, employment, or compliance use.
Enter job values, review the estimate, then use the decision hints before ordering or quoting.
sagitta = r - sqrt(r^2 - (c/2)^2)The sagitta is the height between the chord midpoint and the arc, derived from a right triangle inside the circle.
Chord length cannot exceed the diameter.
Keep more decimals whenever this result will be reused in another formula, drawing step, or comparison instead of being rounded once at the end.