Finding the exact center of a circular board may seem simple, but when it comes to precision tasks like turning, fine drilling, or CNC operations, even a small error can cause critical misalignment. This post introduces four professional-level techniques to locate the center of a circle accurately.     1. Perpendicular Bisector Method Pick three random points on the edge of the circle and connect them to form a triangle. Then, draw the perpendicular bisector of each side of the triangle. The point where all three bisectors intersect is the exact center of the circle. This method is ideal when direct diameter measurements are difficult. 2. Compass and Square Method Use a compass to draw arcs from two points on the circle with equal radius. Where those arcs intersect, draw a straight line through the points. This method is useful for large circular panels or layout design before cutting.     3. CAD-Based Coordinate Method...