Speeds and Feeds Calculator
Calculate spindle speed and feed rate for milling or drilling.
These values are conservative starting points for HSS (high-speed steel) tooling. Carbide tooling can typically run 2-4x faster — adjust based on your tool's coating and cutting conditions.
Results
Enter values to see spindle speed and feed rate.
Usage examples
Setting up a new milling job
Enter the tool diameter and material to quickly get a starting spindle speed and feed rate to dial into your mill.
Quickly working out drilling parameters
Enter the drill's flute count (usually 2) and diameter to calculate the spindle speed and feed rate needed for drilling.
Comparing cutting speed across materials
See how much the recommended spindle speed changes for the same tool diameter between materials like aluminum and stainless steel.
Frequently asked questions
Can I trust the cutting speed values shown here exactly?
No. These are just conservative starting points for HSS tooling — the real optimal value depends heavily on your tool manufacturer, coating, coolant, and machine rigidity. Adjust using your tool manufacturer's catalog and your own experience.
Can I use these values for carbide tooling?
Carbide tooling can typically handle 2-4x higher cutting speeds than HSS. Select 'Custom' and enter the value recommended by your tool manufacturer.
How do I choose the chip load per tooth?
This varies a lot by tool diameter, material, and the tool manufacturer's specification. The default here is just a general starting point — check your tool's spec sheet, or start low and work up.
Can I use the same formula for milling and drilling?
The spindle speed (RPM) and feed rate formulas are the same for both. The main difference is that drills typically have a fixed flute count of 2.