RPM and Surface Speed Converter
Convert cutter-edge surface speed and spindle RPM using the nominal diameter of a cylindrical milling cutter. Enter your own tool-maker value; this tool does not select a cutting speed.
Input values
mm
m/min
Results
Formulas & Notes
Metric: RPM = 1000 × Vc ÷ (π × D). Imperial: RPM = 12 × SFM ÷ (π × D). The reverse operation uses the same circumference relationship; ball-nose effective diameter and radial engagement require separate review.
