rpm
Theoretical speed before adapting to the machine.Machining calculator · Drilling, turning and milling
Cutting speed, RPM and feed rate
Calculate spindle speed and feed rate from diameter, cutting speed, and feed per revolution or per tooth.
Created v1.0
By Thibaut Grzelak, Mechanical Analysis Engineer
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Calculation inputs
Results up to date.
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Diagram
n = 1000 · Vc / (π · D)
Value guide
In drilling, D is the drill diameter and f is feed per revolution.
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Results
mm/min
Theoretical linear travel rate.mm/rev
Input value for drilling.Always check the tool manufacturer’s data, work material, rigidity, coolant and machine limits.
∑View calculation detailsFormulas, units and numerical substitutionOpen ↓
Spindle speed
n = 1000 × 25 / (π × 10)
Feed rate Vf
Vf = n × f
ⓘ Indicative kinematic calculation: it does not replace the tool manufacturer’s cutting data.
Formulas by operation
One common relation, operation-specific feed
| Operation | Diameter D | Feed input | Feed rate Vf |
|---|---|---|---|
| Drilling | Drill diameter | f (mm/rev) | Vf = n · f |
| Turning | Machined diameter | f (mm/rev) | Vf = n · f |
| Milling | Cutter diameter | fz (mm/tooth) | Vf = n · z · fz |
Method
How to use the calculator
- Choose the operation and unit system.
- Enter diameter and cutting speed from the tool data sheet.
- Add feed per revolution or, for milling, feed per tooth and tooth count.
- Adapt RPM and feed to the settings actually available on the machine.
Understand
What is the difference between Vc, n, f and Vf?
Vc is tangential speed at the tool or workpiece edge. n is spindle rotation. f or fz is feed load per revolution or tooth. Vf is the resulting linear travel per minute.
Manufacturer references
Formulas and limits of use
- Sandvik Coromant — drilling formulas
- Sandvik Coromant — turning formulas
- Sandvik Coromant — milling formulas
The kinematic formulas are general. Cutting speed and feed values remain specific to the tool, grade, work material and actual conditions.