Comprehensive Drill Chart (Up to 1″)
Standard Sizes
| Tap Size | Major Diameter | Threads Per Inch | Tap Drill | Clearance Drill | Reamer Size |
|---|---|---|---|---|---|
| #0 | 0.060″ | 80 | 3/64″ (0.047″) | 0.073″ | 1/16″ (0.062″) |
| #1 | 0.073″ | 72 | 53 (0.059″) | 0.073″ | 47 (0.078″) |
| #2 | 0.086″ | 64 | 50 (0.070″) | 0.086″ | 43 (0.089″) |
| #3 | 0.099″ | 56 | 47 (0.078″) | 0.089″ | 37 (0.104″) |
| #4 | 0.112″ | 48 | 44 (0.086″) | 0.098″ | 31 (0.120″) |
| #5 | 0.125″ | 44 | 40 (0.098″) | 0.104″ | 29 (0.136″) |
| #6 | 0.138″ | 40 | 33 (0.113″) | 0.120″ | 25 (0.152″) |
| #8 | 0.164″ | 36 | 29 (0.136″) | 0.147″ | 17 (0.173″) |
| #10 | 0.190″ | 32 | 25 (0.152″) | 0.161″ | 9 (0.196″) |
| #12 | 0.216″ | 28 | 16 (0.177″) | 0.189″ | 2 (0.221″) |
| 1/4″ | 0.25″ | 20 | 13/64″ (0.203″) | 17/64″ (0.266″) | 0.255″ |
| 5/16″ | 0.3125″ | 18 | 5/16″ (0.3125″) | 21/64″ (0.328″) | 0.318″ |
| 3/8″ | 0.375″ | 16 | 21/64″ (0.328″) | 25/64″ (0.391″) | 0.382″ |
| 7/16″ | 0.4375″ | 14 | 25/64″ (0.391″) | 29/64″ (0.453″) | 0.445″ |
| 1/2″ | 0.5″ | 13 | 27/64″ (0.422″) | 33/64″ (0.516″) | 0.508″ |
| 9/16″ | 0.5625″ | 12 | 31/64″ (0.484″) | 37/64″ (0.578″) | 0.571″ |
| 5/8″ | 0.625″ | 11 | 17/32″ (0.531″) | 41/64″ (0.641″) | 0.634″ |
| 3/4″ | 0.75″ | 10 | 21/32″ (0.656″) | 49/64″ (0.766″) | 0.759″ |
| 1″ | 1.0″ | 8 | 29/32″ (0.906″) | 1.005″ | 1.008″ |
Metric Sizes (Up to 1″)
| Tap Size | Major Diameter | Pitch (mm) | Tap Drill | Reamer Size | Decimal Equivalent |
|---|---|---|---|---|---|
| M1.4×0.3 | 1.4 mm | 0.3 | 1.1 mm | 1.4 mm | 0.0551″ |
| M1.5×0.35 | 1.5 mm | 0.35 | 1.15 mm | 1.5 mm | 0.0591″ |
| M1.6×0.35 | 1.6 mm | 0.35 | 1.25 mm | 1.6 mm | 0.0630″ |
| M1.8×0.35 | 1.8 mm | 0.35 | 1.45 mm | 1.8 mm | 0.0709″ |
| M2x0.4 | 2.0 mm | 0.4 | 1.6 mm | 2.0 mm | 0.0787″ |
| M2.2×0.45 | 2.2 mm | 0.45 | 1.75 mm | 2.2 mm | 0.0866″ |
| M2.5×0.45 | 2.5 mm | 0.45 | 2.05 mm | 2.5 mm | 0.0984″ |
| M3x0.5 | 3.0 mm | 0.5 | 2.7 mm | 3.0 mm | 0.1181″ |
| M4x0.35 | 4.0 mm | 0.35 | 3.6 mm | 4.0 mm | 0.1575″ |
| M4x0.5 | 4.0 mm | 0.5 | 3.5 mm | 4.0 mm | 0.1575″ |
| M5x0.5 | 5.0 mm | 0.5 | 4.5 mm | 5.0 mm | 0.1969″ |
| M5x0.8 | 5.0 mm | 0.8 | 4.2 mm | 5.0 mm | 0.1969″ |
| M6x0.5 | 6.0 mm | 0.5 | 5.5 mm | 6.0 mm | 0.2362″ |
| M6x0.75 | 6.0 mm | 0.75 | 5.25 mm | 6.0 mm | 0.2362″ |
| M6x1.0 | 6.0 mm | 1.0 | 5.0 mm | 6.0 mm | 0.2362″ |
| M7x0.75 | 7.0 mm | 0.75 | 6.25 mm | 7.0 mm | 0.2756″ |
| M8x1.25 | 8.0 mm | 1.25 | 6.8 mm | 8.0 mm | 0.3150″ |
| M24x3.0 | 24.0 mm | 3.0 | 21.0 mm | 24.0 mm | 0.9449″ |
| M27x3.0 | 27.0 mm | 3.0 | 24.0 mm | 27.0 mm | 1.0630″ |