Edge chamfer
Angle is measured from the flat workpiece face. At 45°, radial width C and axial depth Z are equal.
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Chamfer and countersink calculator
Convert chamfer width to axial depth, calculate hole-countersink geometry or find the chamfer-mill plunge required for a target diameter.
Inside and outside edges60–120° countersinksFlat-tip chamfer millsLocal calculations
Unambiguous geometry
Three tasks with three clear conventions
Most mistakes come from angle convention or confusing radial width with axial depth. Each calculation mode explains its convention directly beside the result.
Hole countersink
Enter hole diameter, countersink diameter and full included angle. The result gives the theoretical cone depth.
Chamfer mill
This mode includes the tool's flat tip and calculates the plunge needed to reach a target cutting diameter.
FAQ
Frequently asked questions
How do I calculate the depth of a 45° chamfer?
At 45°, tangent equals 1, so axial depth Z equals radial chamfer width C.
Which angle should I enter for a 90° countersink?
Enter the full included angle: 90°. The calculator automatically uses half of it in the geometry formula.
Can I calculate an outside-diameter chamfer?
Yes. Select outside edge. The calculator subtracts twice the radial chamfer width from the base diameter.
Why is tool-tip diameter required?
A chamfer mill often has a flat rather than a perfect point. The flat changes the relationship between plunge Z and cutting diameter.
Can the result be entered directly into CNC code?
It is theoretical geometry. Verify actual tool measurement, corner radius, datum and drawing requirements before use.
Custom tools
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NCTune develops postprocessors, automation and dedicated tools for Siemens NX CAM and production environments.