Set Up Spindle Speed
Enter the tool diameter and target SFM. Keep the diameter in inches for the imperial formula shown here.
Spindle Speed RPM Calculator
Calculate CNC spindle RPM from tool diameter and cutting speed.
Metrik MFG / Spindle SpeedREADY
Spindle Speed RPM Calculator
INPUTVALUEOUTPUT
Primary input01
Process setting02
Calculated output03
CALCULATION STATUSREADY TO CALCULATEEnter values below to generate results
STANDARD MODE
READY TO CALCULATE
Spindle Speed RPM Calculator
Advanced Engineering
PRACTICAL CONTEXT
Using the result in real shop work
This calculator converts a target surface speed and tool diameter into spindle speed. It is useful for milling, drilling, and other rotating-tool operations where the cutting speed is known.
Where This Result Helps
Use the result when selecting spindle speed, checking an existing setup, or comparing recommended cutting speeds.
What Can Distort the Result
Using cutter diameter instead of effective diameter, mixing metric diameter with imperial SFM, or forgetting that different operations can use different cutting-speed recommendations.
ENGINEERING METHOD
How the spindle speed calculation works.
FORMULARPM = 3.82 × SFM ÷ diameter.
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