Feeds and Speeds Calculator
Calculate spindle speed (RPM) and feed rate for CNC milling and drilling. Pick a material to load conservative starting values, switch between inch and metric, and print a shop ticket.
Milling feeds and speeds
Power is a rough estimate using the material unit power factor. Verify against your spindle rating.
Spindle speed
- RPM
Feed rate
- IPM
Material removal rate
- in3/min
Approx. spindle power
- HP
Editorial estimate only
These are conservative starting points, not a guarantee. Verify against manufacturer tooling data and your machine manual. Confirm spindle power, workholding and coolant before cutting.
Milling calculator
End mill RPM and feed rate with chip load and optional MRR and power.
Drilling calculator
Twist drill RPM and feed rate from surface speed and feed per revolution.
SFM to RPM
Convert surface feet per minute (or m/min) to spindle speed.
Chip load
Solve chip load per tooth from feed rate, RPM and number of flutes.
How it works
- Choose a material to load recommended surface speed and chip load.
- Enter your tool diameter and number of flutes.
- RPM is calculated from surface speed and diameter.
- Feed rate is calculated from RPM, chip load and flute count.
- Optional material removal rate and power are rough estimates.
Material presets
Presets cover aluminum 6061, mild steel 1018, stainless 304, brass C360, acrylic, titanium 6Al-4V and cast iron. Values are editorial estimates based on public machining references, not lab calibrated data.
Browse the material library