RPM Calculator (Metric)
Calculate rotational speed from surface speed and diameter.
Formula: n = (60 × v) / (π × D)
These calculators are intended as quick reference tools only. Results are approximate and should not replace professional engineering judgment, calculations, or validation.
RPM Calculator (Metric)
This page provides a revolutions per minute (RPM) calculator for engineering and machining applications.
The tool calculates rotational speed based on diameter and surface speed.
All inputs and results use the metric system.
Purpose of the Calculator
The calculator helps determine rotational speed (RPM) of shafts, tools, and gears.
It is commonly used in machining, CNC programming, and mechanical design.
The tool works by converting surface speed and diameter into RPM.
Typical Applications
RPM calculations are used in many engineering areas:
- CNC machining and milling
- Lathe and turning operations
- Gear systems and power transmission
- Motor and shaft speed analysis
This calculator supports fast technical checks and design work.
Calculation Method
The calculation follows standard engineering formulas.
Formula:
n = (60 × v) / (π × D)
Where:
- n = RPM (revolutions per minute)
- v = surface speed (m/s)
- D = diameter (m)
Alternative machining formula:
n = (1000 × Vc) / (π × D)
Where:
- Vc = cutting speed (m/min)
- D = diameter (mm)
Usage Notes
The calculator runs directly in the browser.
No installation is required.
It works on desktop and mobile devices.
Results are displayed instantly after input.
Disclaimer
This calculator is for informational use only.
Always verify results before using them in production or safety-critical applications.
We are not responsible for decisions based on these calculations.