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Fillet tangent geometry calculator
This tool models a fillet tangent to two intersecting straight lines, with an interior angle between 0° and 180°. It reports positive distances from the vertex. It does not select a concave or convex toolpath side or apply cutter compensation.
Formula and inputs
Tangent distance = R / tan(θ/2); centre distance along bisector = R / sin(θ/2).
Worked example
For a 5 mm radius in a 90° corner, tangent distance is 5 mm, centre distance is 7.071 mm and sweep is 90°.
Use the result in your setup
Confirm the input dimensions and unit system against your drawing before calculating. Keep full precision during a calculation and round only the final value to suit the measurement or programming requirement. A numerical result does not account for a machine’s complete setup, workholding or control configuration.