Shaft Speed Calculator
Enter a cutting diameter or pulley pitch diameter and the rotational speed of that same pulley. Diameter must be positive; rpm may be zero.
π × D(mm) × rpm ÷ 1000; m/s = m/min ÷ 60. Same pulley; pitch diameter; no slip. Peripheral speed only: no safety, rating or cutting recommendation.
Peripheral speed (m/s):
Peripheral / no-slip belt speed (m/min):
A QUICK WALKTHROUGH
How to use this tool
- Enter a positive diameter in mm.
- Enter nonnegative rpm for the same pulley.
- Calculate m/min and m/s, then copy the TXT report.
Formula and units
v = π × D(mm) × rpm ÷ 1000 in m/min; divide by 60 for m/s. At zero rpm both speeds are zero.
Diameter and no-slip model
Use the cutting diameter for surface speed, or pulley pitch diameter for belt speed. Pair diameter and rpm from the same pulley. Belt speed assumes no slip; outside diameter can give a different estimate.
Precision and scope
Outputs use JavaScript binary floating point and display 8 significant digits. Reports include raw and actual numeric inputs, units and assumptions. This calculates speed only and does not determine belt ratings, safety or cutting settings.
GOOD TO KNOW
Common questions
Which diameter is appropriate?
Use the diameter where speed is evaluated. For belts use pitch diameter, not outside diameter; calculate stepped or tapered diameters separately.
Can rpm be zero?
Yes. A positive diameter with zero rpm produces 0 m/min and 0 m/s. Negative rpm is outside this speed-magnitude model.
Does the result establish a safe belt speed?
No. No-slip speed alone cannot establish safety or suitability. Belt type, slip, ratings and machine conditions must be evaluated separately.