Tapping speeds and feeds (RPM, feed rate)
Spindle speed and feed rate for tapping. The feed rate is pitch × RPM (rigid / synchronous tapping).
⟟Tapping calculator
Spindle speed n—rpm
Feed rate Vf—mm/min
n = 1000 × Vc ÷ (π × D) Vf = P × n
Notes
- If the feed rate does not match pitch × RPM, the thread is damaged or the tap breaks.
- M8 coarse pitch is 1.25 mm, fine pitch 1.0 mm, and so on. Tap drill sizes are in the metric thread tables.
All values are guides. Start from the tool maker’s recommended cutting data and adjust for your machine, workholding and coolant. Calculations run in your browser; nothing you enter is sent anywhere.