CNC Feed Rate & Feed per Tooth Calculator
Calculate table feed, feed per tooth or RPM for milling.
Results
Table feed
- Basic feed-per-tooth calculation. Actual chip thickness can differ with cutter geometry, radial engagement and chip thinning.
This calculator uses the basic feed-per-tooth relationship. Actual chip thickness may differ due to cutter geometry, radial engagement and chip thinning. It does not apply chip-thinning compensation or recommend feeds. Use tool manufacturer data and verify machine and tooling limits.
Formula · How it works
Formula
Vf = n × Z × fzfz = Vf / (n × Z)n = Vf / (Z × fz)Vf = n × Z × fz, where n is rev/min and Z is tooth or flute count. With fz in mm/tooth, Vf is mm/min; with fz in in/tooth, Vf is in/min (IPM). Inverse formulas are fz = Vf/(nZ) and n = Vf/(Zfz). Internally, feed per tooth uses m and feed rate uses m/s, including the conversion from minutes to seconds.
Worked example
At 6,000 rpm with 4 flutes and 0.05 mm/tooth, table feed is 6,000 × 4 × 0.05 = 1,200 mm/min = 1.20 m/min ≈ 47.24 in/min. Using that feed, RPM and flute count returns 0.05 mm/tooth.
How it works
Feed per tooth is the distance the table advances for each cutting tooth. Multiplying by flute count gives feed per revolution, and multiplying by RPM gives table feed per minute. Increasing RPM at a constant table feed reduces feed per tooth.
Common questions
Is feed per tooth always the actual chip thickness?
No. Feed per tooth is commonly called chip load, but actual chip thickness also depends on cutter geometry and radial engagement. This calculator does not compensate for chip thinning.
Can flute count contain a fraction?
No. Enter the number of cutting teeth or flutes as a positive integer, such as 2, 3 or 4.
Why is zero RPM rejected when calculating feed per tooth?
RPM is a divisor in that mode, so it must be positive. Similarly, feed per tooth must be positive when calculating RPM. Zero table feed is allowed and returns zero feed per tooth or RPM when the other divisors are valid.