Cutting Speed Calculator
This cutting speed calculator turns surface speed and tool diameter into spindle RPM, or RPM into cutting speed, and can add the table feed rate for milling, drilling and turning.
Example: What to calculate: RPM from cutting speed · Cutting speed vc 100 m/min · Tool or workpiece diameter 10 mm · Number of cutting edges 2 teeth · Feed per tooth fz 0.05 mm → Result: Spindle speed: 3,183 rpm. Source: Wikipedia – Schnittgeschwindigkeit (vc = π · d · n). Updated: .
How it is calculated
A 10 mm cutter at vc = 100 m/min needs about 3,183 revolutions per minute. Cutting speed is how fast the cutting edge travels past the material at the circumference.
How it is calculated
Surface speed follows from diameter and spindle speed: vc = π · d · n / 1000, with d in millimetres and vc in metres per minute. Rearranged, the spindle speed is n = vc · 1000 / (π · d). From spindle speed, feed per tooth and number of teeth you get the feed rate vf = n · fz · z in millimetres per minute. A smaller diameter needs a higher spindle speed for the same vc.
Notes
- The right vc comes from the tool manufacturer for your material and cutting-material combination.
- If the machine cannot reach the calculated speed, pick the next lower step.
- For wood and plastics, melting and burning limit the speed as much as the machine does.
Frequently asked questions
How do you calculate cutting speed?
With vc = π · d · n / 1000, where d is the diameter in mm, n the spindle speed in rpm and vc the result in m/min.
How do I get RPM from cutting speed?
n = vc · 1000 / (π · d). Choose the mode “RPM from cutting speed” in the calculator.
Where do I find the right vc value?
In the catalogue or data sheets of the tool maker, which list guide values per workpiece material and cutting material.
What is feed per tooth?
The distance the workpiece advances per tooth per revolution. With spindle speed and tooth count it gives the feed rate in mm/min.
Sources and legal basis
- Wikipedia – Schnittgeschwindigkeit (vc = π · d · n)
- Wikipedia – Speeds and feeds (spindle speed, feed per tooth)
As of: · Editorial policy
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