CNC chip load chart

Chip load per tooth, in inches, for solid carbide up-cut and down-cut spiral router bits, cutting as deep as the bit is wide. Each maker's own figure, the value the CNC feeds and speeds calculator starts from, and what stands behind it.

Chip loads are for a cut as deep as the bit is wide. At 2 × the diameter take at least 25% off; at 3 × the diameter at least 50%.
3 sources agree , sources [1, 2, 3]

Sources

Freud / Diablo, Get the most out of your Freud bits by routing at ideal feed rates and speeds: chip loads for Freud solid carbide router bits (2017), read 2026-11-07
Amana Tool, 2 Flute Solid Carbide Spiral Plunge for Solid Wood: CNC speed chart (18,000 RPM, depth 1 × D), read 2026-11-07
Onsrud, Cutting data sheets: softwood, hardwood, MDF, soft and hard plywood, chip load per tooth by series (series 56-200 row; hosted by WOODWEB), read 2026-11-07

Softwood (pine, fir, cedar)

Bit Ø	Freud / Diablo	Amana Tool	Onsrud	Start	Basis
1/8 in	0.004–0.006	0.003–0.005	0.004–0.006	0.005	Median of 3 sources
3/16 in	0.007–0.009	0.004–0.006	0.005–0.007	0.006	Median of 3 sources
1/4 in	0.01–0.012	0.005–0.007	0.006–0.008	0.007	Median of 3 sources
5/16 in	0.013–0.0155	0.005–0.007	0.006–0.008	0.007	Median of 3 sources
3/8 in	0.016–0.019	0.006–0.008	0.007–0.009	0.008	Median of 3 sources
1/2 in	0.02–0.023	0.007–0.009	0.008–0.01	0.009	Median of 3 sources

Hardwood (oak, maple, walnut)

Bit Ø	Freud / Diablo	Amana Tool	Onsrud	Start	Basis
1/8 in	0.002–0.005	0.003–0.005	0.003–0.005	0.004	Median of 3 sources
3/16 in	0.005–0.008	0.004–0.006	0.004–0.006	0.005	Median of 3 sources
1/4 in	0.008–0.011	0.005–0.007	0.005–0.007	0.006	Median of 3 sources
5/16 in	0.011–0.0135	0.005–0.007	0.005–0.007	0.006	Median of 3 sources
3/8 in	0.014–0.016	0.006–0.008	0.006–0.008	0.007	Median of 3 sources
1/2 in	0.018–0.021	0.007–0.009	0.007–0.009	0.008	Median of 3 sources

MDF and particleboard

Bit Ø	Freud / Diablo	Amana Tool	Onsrud	Start	Basis
1/8 in	0.004–0.007	–	0.003–0.005	0.0048	Only two sources publish this: Freud / Diablo and Onsrud
3/16 in	0.0085–0.012	–	0.004–0.006	0.005	Two sources disagree: Freud / Diablo 0.01025, Onsrud 0.005
1/4 in	0.013–0.017	–	0.005–0.007	0.006	Two sources disagree: Freud / Diablo 0.015, Onsrud 0.006
5/16 in	0.0155–0.019	–	0.005–0.007	0.006	Two sources disagree: Freud / Diablo 0.01725, Onsrud 0.006
3/8 in	0.018–0.021	–	0.006–0.008	0.007	Two sources disagree: Freud / Diablo 0.0195, Onsrud 0.007
1/2 in	0.023–0.027	–	0.007–0.009	0.008	Two sources disagree: Freud / Diablo 0.025, Onsrud 0.008

Plywood

Bit Ø	Freud / Diablo	Amana Tool	Onsrud	Start	Basis
1/8 in	0.003–0.005	–	0.003–0.005	0.004	Only two sources publish this: Freud / Diablo and Onsrud
3/16 in	0.0045–0.007	–	0.004–0.006	0.0054	Only two sources publish this: Freud / Diablo and Onsrud
1/4 in	0.006–0.009	–	0.005–0.007	0.0068	Only two sources publish this: Freud / Diablo and Onsrud
5/16 in	0.0105–0.0135	–	0.005–0.007	0.009	Only two sources publish this: Freud / Diablo and Onsrud
3/8 in	0.015–0.018	–	0.006–0.008	0.007	Two sources disagree: Freud / Diablo 0.0165, Onsrud 0.007
1/2 in	0.018–0.021	–	0.007–0.009	0.008	Two sources disagree: Freud / Diablo 0.0195, Onsrud 0.008

Reading the chart

Sizes between a maker's printed sizes are read on a straight line between them, never past the ends of its table. Amana prints one row for softwood and hardwood together, and no MDF or plywood row for these bits, so those two materials rest on Freud and Onsrud alone. Onsrud's figures are its series 56-200 row, the one series printed for every material. Where two makers are more than two times apart, as Freud and Onsrud are for MDF, the tag says they disagree and the calculator starts at the lower.