Drill diameters for tappings

Métrique  Métrique fin

Metric 

Thread Pitch Drill diameter
M1 0.25 0.75
M1.1 0.25 0.85
M1.2 0.25 0.95
M1.4 0.3 1.1
M1.6 0.35 1.25
M2 0.4 1.6
M2.5 0.45 2.05
M3 0.5 2.5
M4 0.7 3.3
M5 0.8 4.2
M6 1 5
M7 1 6
M8 1.25 6.8
M10 1.5 8.5
M12 1.75 10.25
M14 2 12
M16 2 14
M18 2.5 15.5
M20 2.5 17.5
M22 2.5 19.5
M24 3 21
M27 3 24
M30 3.5 26.5
M33 3.5 29.5
M36 4 32
M39 4 35
M42 4.5 37.5
M45 4.5 41.5
M48 5 43
M52 5 47
M56 5.5 50.5
M60 5.5 54.5
M64 6 58

From wikipédia https://fr.wikipedia.org/wiki/Filetage_m%C3%A9trique

Metric fine

Thread Pitch Drill diameter
M3 x 0.35 2.65
M3.5 x 0.35 3.15
M4 x 0.35 3.65
M4 x 0.5 3.5
M5 x 0.5 4.5
M6 x 0.5 5.5
M6 x 0.75 5.2
M7 x 0.75 6.2
M8 x 0.5 7.5
M8 x 0.75 7.2
M8 x 1 7
M9 x 1 8
M10 x 0.5 9.5
M10 x 0.75 9.2
M10 x 1 9
M10 x 1.25 8.8
M11 x 1 10
M12 x 0.75 10.2
M12 x 1 11
M12 x 1.125 10.8
M12 x 1.5 10.5
M13 x 1 12
M13 x 1.5 11.5
M13 x 1.75 11.2
M14 x 1 13
M14 x 1.25 12.8
M14 x 1.5 12.5
M15 x 1 14
M15 x 1.5 13.5
M15 x 2 13
M16 x 1 15
M16 x 1.5 14.5
M18 x 1 17
M18 x 1.5 16.5
M18 x 2 16
M20 x 1 19
M20 x 1.5 18.5
M20 x 2 18
M22 x 1 21
M22 x 1.5 20.5
M22 x 2 20
M24 x 1 23
M24 x 1.5 22.5
M24 x 2 22

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