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GeometryCircles

Tangent Length Calculator

Find the tangent length from an external point.

Controls

5
13

Live result

Point lies
Outside the circle
Tangent length
12
Number of tangents
2
Tangents from an external pointPoint lies: Outside the circle
Pr = 5
Click to start animation

The tangent at any point is perpendicular to the radius, so OP² = OT² + PT².