Threading & Hole Sizing
탭 드릴 기초홀 규격표 (미터법 & 인치)
Pre-drill hole sizes for ~75% thread engagement across Metric, UNC, UNF, and NPT pipe threads.
Showing 43 threads
| Thread Size | Standard | Major Dia (mm / in) | Pitch / TPI | Cut Tap Drill (mm / in) | Form Tap Drill (mm / in) | Clearance Hole | Calculate |
|---|---|---|---|---|---|---|---|
| M2 x 0.4 | Metric Coarse | 2.00 mm (0.079") | 0.40 mm (63.5 TPI) | 1.60 mm (0.0630") | 1.80 mm (0.0709") | 2.40 mm | Engage % → |
| M2.5 x 0.45 | Metric Coarse | 2.50 mm (0.098") | 0.45 mm (56.4 TPI) | 2.05 mm (0.0807") | 2.30 mm (0.0906") | 2.90 mm | Engage % → |
| M3 x 0.5 | Metric Coarse | 3.00 mm (0.118") | 0.50 mm (50.8 TPI) | 2.50 mm (0.0984") | 2.80 mm (0.1102") | 3.40 mm | Engage % → |
| M4 x 0.7 | Metric Coarse | 4.00 mm (0.158") | 0.70 mm (36.3 TPI) | 3.30 mm (0.1299") | 3.70 mm (0.1457") | 4.50 mm | Engage % → |
| M5 x 0.8 | Metric Coarse | 5.00 mm (0.197") | 0.80 mm (31.8 TPI) | 4.20 mm (0.1654") | 4.65 mm (0.1831") | 5.50 mm | Engage % → |
| M6 x 1.0 | Metric Coarse | 6.00 mm (0.236") | 1.00 mm (25.4 TPI) | 5.00 mm (0.1969") | 5.50 mm (0.2165") | 6.60 mm | Engage % → |
| M8 x 1.25 | Metric Coarse | 8.00 mm (0.315") | 1.25 mm (20.3 TPI) | 6.80 mm (0.2677") | 7.40 mm (0.2913") | 9.00 mm | Engage % → |
| M10 x 1.5 | Metric Coarse | 10.00 mm (0.394") | 1.50 mm (16.9 TPI) | 8.50 mm (0.3346") | 9.30 mm (0.3661") | 11.00 mm | Engage % → |
| M12 x 1.75 | Metric Coarse | 12.00 mm (0.472") | 1.75 mm (14.5 TPI) | 10.20 mm (0.4016") | 11.20 mm (0.4409") | 13.50 mm | Engage % → |
| M14 x 2.0 | Metric Coarse | 14.00 mm (0.551") | 2.00 mm (12.7 TPI) | 12.00 mm (0.4724") | 13.00 mm (0.5118") | 15.50 mm | Engage % → |
| M16 x 2.0 | Metric Coarse | 16.00 mm (0.630") | 2.00 mm (12.7 TPI) | 14.00 mm (0.5512") | 15.00 mm (0.5906") | 17.50 mm | Engage % → |
| M20 x 2.5 | Metric Coarse | 20.00 mm (0.787") | 2.50 mm (10.2 TPI) | 17.50 mm (0.6890") | 18.80 mm (0.7402") | 22.00 mm | Engage % → |
| M24 x 3.0 | Metric Coarse | 24.00 mm (0.945") | 3.00 mm (8.5 TPI) | 21.00 mm (0.8268") | 22.50 mm (0.8858") | 26.00 mm | Engage % → |
| M8 x 1.0 | Metric Fine | 8.00 mm (0.315") | 1.00 mm (25.4 TPI) | 7.00 mm (0.2756") | 7.50 mm (0.2953") | 9.00 mm | Engage % → |
| M10 x 1.0 | Metric Fine | 10.00 mm (0.394") | 1.00 mm (25.4 TPI) | 9.00 mm (0.3543") | 9.50 mm (0.3740") | 11.00 mm | Engage % → |
| M10 x 1.25 | Metric Fine | 10.00 mm (0.394") | 1.25 mm (20.3 TPI) | 8.80 mm (0.3465") | 9.40 mm (0.3701") | 11.00 mm | Engage % → |
| M12 x 1.25 | Metric Fine | 12.00 mm (0.472") | 1.25 mm (20.3 TPI) | 10.80 mm (0.4252") | 11.40 mm (0.4488") | 13.50 mm | Engage % → |
| M12 x 1.5 | Metric Fine | 12.00 mm (0.472") | 1.50 mm (16.9 TPI) | 10.50 mm (0.4134") | 11.30 mm (0.4449") | 13.50 mm | Engage % → |
| #2-56 UNC | UNC | 2.18 mm (0.086") | 0.45 mm (56.0 TPI) | 1.80 mm (0.0700") | 1.98 mm (0.0781") | 2.45 mm | Engage % → |
| #4-40 UNC | UNC | 2.84 mm (0.112") | 0.64 mm (40.0 TPI) | 2.25 mm (0.0890") | 2.55 mm (0.1015") | 3.25 mm | Engage % → |
| #6-32 UNC | UNC | 3.51 mm (0.138") | 0.79 mm (32.0 TPI) | 2.77 mm (0.1065") | 3.15 mm (0.1240") | 3.80 mm | Engage % → |
| #8-32 UNC | UNC | 4.17 mm (0.164") | 0.79 mm (32.0 TPI) | 3.45 mm (0.1360") | 3.80 mm (0.1500") | 4.50 mm | Engage % → |
| #10-24 UNC | UNC | 4.83 mm (0.190") | 1.06 mm (24.0 TPI) | 3.80 mm (0.1495") | 4.35 mm (0.1719") | 5.10 mm | Engage % → |
| 1/4-20 UNC | UNC | 6.35 mm (0.250") | 1.27 mm (20.0 TPI) | 5.10 mm (0.2010") | 5.80 mm (0.2280") | 6.75 mm | Engage % → |
| 5/16-18 UNC | UNC | 7.94 mm (0.313") | 1.41 mm (18.0 TPI) | 6.53 mm (0.2570") | 7.30 mm (0.2874") | 8.40 mm | Engage % → |
| 3/8-16 UNC | UNC | 9.53 mm (0.375") | 1.59 mm (16.0 TPI) | 7.94 mm (0.3125") | 8.85 mm (0.3480") | 10.00 mm | Engage % → |
| 7/16-14 UNC | UNC | 11.11 mm (0.438") | 1.81 mm (14.0 TPI) | 9.35 mm (0.3680") | 10.35 mm (0.4062") | 11.80 mm | Engage % → |
| 1/2-13 UNC | UNC | 12.70 mm (0.500") | 1.95 mm (13.0 TPI) | 10.72 mm (0.4219") | 11.80 mm (0.4646") | 13.50 mm | Engage % → |
| 5/8-11 UNC | UNC | 15.88 mm (0.625") | 2.31 mm (11.0 TPI) | 13.49 mm (0.5312") | 14.80 mm (0.5827") | 17.00 mm | Engage % → |
| 3/4-10 UNC | UNC | 19.05 mm (0.750") | 2.54 mm (10.0 TPI) | 16.67 mm (0.6562") | 17.90 mm (0.7031") | 20.20 mm | Engage % → |
| 1-8 UNC | UNC | 25.40 mm (1.000") | 3.17 mm (8.0 TPI) | 22.22 mm (0.8750") | 23.80 mm (0.9375") | 27.00 mm | Engage % → |
| #10-32 UNF | UNF | 4.83 mm (0.190") | 0.79 mm (32.0 TPI) | 4.04 mm (0.1590") | 4.45 mm (0.1752") | 5.10 mm | Engage % → |
| 1/4-28 UNF | UNF | 6.35 mm (0.250") | 0.91 mm (28.0 TPI) | 5.49 mm (0.2130") | 5.95 mm (0.2344") | 6.75 mm | Engage % → |
| 5/16-24 UNF | UNF | 7.94 mm (0.313") | 1.06 mm (24.0 TPI) | 6.91 mm (0.2720") | 7.50 mm (0.2953") | 8.40 mm | Engage % → |
| 3/8-24 UNF | UNF | 9.53 mm (0.375") | 1.06 mm (24.0 TPI) | 8.51 mm (0.3320") | 9.10 mm (0.3583") | 10.00 mm | Engage % → |
| 7/16-20 UNF | UNF | 11.11 mm (0.438") | 1.27 mm (20.0 TPI) | 9.92 mm (0.3906") | 10.60 mm (0.4173") | 11.80 mm | Engage % → |
| 1/2-20 UNF | UNF | 12.70 mm (0.500") | 1.27 mm (20.0 TPI) | 11.51 mm (0.4531") | 12.20 mm (0.4803") | 13.50 mm | Engage % → |
| 1/8-27 NPT | NPT | 10.29 mm (0.405") | 0.94 mm (27.0 TPI) | 8.73 mm (0.3438") | — | 10.50 mm | Engage % → |
| 1/4-18 NPT | NPT | 13.72 mm (0.540") | 1.41 mm (18.0 TPI) | 11.11 mm (0.4375") | — | 14.00 mm | Engage % → |
| 3/8-18 NPT | NPT | 17.15 mm (0.675") | 1.41 mm (18.0 TPI) | 14.29 mm (0.5625") | — | 17.50 mm | Engage % → |
| 1/2-14 NPT | NPT | 21.34 mm (0.840") | 1.81 mm (14.0 TPI) | 17.86 mm (0.7031") | — | 22.00 mm | Engage % → |
| 3/4-14 NPT | NPT | 26.67 mm (1.050") | 1.81 mm (14.0 TPI) | 23.02 mm (0.9062") | — | 27.50 mm | Engage % → |
| 1-11.5 NPT | NPT | 33.40 mm (1.315") | 2.21 mm (11.5 TPI) | 29.37 mm (1.1562") | — | 34.50 mm | Engage % → |