TAPPING DRILL SIZES

IMPERIAL THREADS

Tap Size

B.S Whit

U.N.F

U.N.C

B.S.F

B.S.P

B.A

Drill Size Drill Size

Drill Size

Drill Size Drill Size

Tap Size

Drill Size

1/16 1.1mm 0 5.1mm

3/32 1.8mm

1/8 2.5mm 11/32 1 4.5mm

5/32 2.9mm 1/8

3/16 3.7mm 5/32 2 5/32

7/32 4.2mm 4.4mm

1/4 13/64 7/32 13/64 5.3mm 15/32 3 3.4mm

5/16 1/4 I 6.5mm 17/64 4 3.0mm

3/8 5/16 21/64 5/16 21/64 19/32 5 2.6mm

7/16 23/64 25/64 9.3mm 3/8 6 2.3mm

1/2 13/32 29/64 27/64 7/16 3/4 7 2.0mm

9/16 15/32 33/64 31/64 1/2 8 1.8mm

5/8 17/32 37/64 17/32 35/64 53/64 9 1.5mm

11/16 19/32 19/32 39/64

3/4 21/32 11/16 21/32 43/64 31/32 10 1.4mm

13/16 23/32 23/32 47/64 11 3/64

7/8 3/4 13/16 49/64 25/32 1-1/8 12 1.0mm

1’ 55/64 15/16 7/8 57/64 1-7/32

1-1/8 63/64 1-3/64 63/64 1-1/64

1-1/4 1-3/32 1-11/64 1-7/64 1-9/64 1-9/16

1-3/8 1-13/64 1-19/64 1-13/64 1-1/4

1-1/2

1-11/32 1-27/64 1-11/32 1- 23/64

1-51/64

1-5/8 1-7/16 1-1/2

1-3/4 1-17/32 1-9/16 1-19/32 2-1/32

2” 1-49/64 1-25/32 1-27/32 2-17/64

METRIC THREADS

Tap size

Pitch

Tapping Drill

M 1.0 .25 1.11mm

M 1.0 .20 1.1mm

M 1.5 .35 1.15mm

M 2.0 .40 1.6mm

M 2.2 .45 1.5mm

M 2.25 .50 1.9mm

M 2.3 .40 1.9mm

M 2.5 .35 2.0mm

M 2.5 .45 2.0mm

M 2.6 .45 2.1mm

M 3.0 .50 2.5mm

M 3.0 .60 2.4mm

M 3.5 .60 2.90mm

M 3.6 .75 2.25mm

M 3.8 .35 2.7mm

M 4.0 .70 3.30mm

M 4.5 .50 4.0mm

M 4.5 .75 3.75mm

M 5.0 .50 4.5mm

M 5.0 .75 4.25mm

M 5.0 .80 4.20mm

M 5.5 .90 4.1mm

M 5.0 1.0 4.0mm

M 5.5 .75 4.75

M 5.5 90 4.6

M 6 .75 5.2mm

M 6 1.0 5.0mm

M 6 1.25 4.8mm

M 7 .5 6.0mm

M 7 .75 6.2mm

M 7 1.0 6.00mm

M 7 1.25 5.8mm

M 8 .75 6.5mm

M 8 1.0 7.00mm

M 8 1.25 6.80mm

M 9 .75 6.25mm

M 9 1.0 8.0mm

M 9 1.25 7.80mm

M 10 .75 9.0mm

M 10 1.0 9.00mm

M 10 1.25 8.80mm

M 10 1.5 8.50mm

M 11 1 10.0mm

M 11 1.25 9.8mm

M 11 1.5 9.50mm

M 12 1 11.25mm

M 12 1.25 11.0mm

M 12 1.5 10.5mm

M 12 1.75 10.3mm

M 13 1.5 11.5mm

M 13 1.75 11.5mm

M 13 2.0 11.0mm

M 14 1.25 12.80mm

M 14 1.5 12.50mm

M 14 2.0 12.00mm

M 16 1.5 14.5mm

M 16 2.0 14.0mm

M 18 1.5 16.5mm

M 18 2.5 15.5mm

M 20 1.5 18.5mm

M 20 2.5 17.5mm

M 22 1.5 20.5mm

M 22 2.5 19.5mm

M 24 2.0 22.0mm

M 24 3.0 21.0mm

M 27 3.0 24.0mm

M 30 3.5 26.5mm

M 33 3.5 29.5mm

M 36 4.0 32.0mm