Area of Sector Calculator: Quickly Compute Circular Segments

Compute a sector’s area, radius, or angle in one click. Enter two known values and the tool applies $$A = rac12 r^{2}theta$$, reporting answers to 8 decimal places—matching the 7.4 × 10⁻⁹ relative error of IEEE-754 double precision (IEEE, 2008). No unit restrictions; just keep them consistent.