| Tap Drill | Clearance Drill | |||||||||
|---|---|---|---|---|---|---|---|---|---|---|
| Aluminum, Brass, Plastics | Steel, Stainless Steel, Iron | Close Fit | Standard Fit | |||||||
| 75% Thread | 50% Thread | |||||||||
| Screw Size | Major Dia (mm) | mm per Thread | Drill Size | Closest Imperial | Drill Size | Closest Imperial | Drill Size | Closest Imperial | Drill Size | Closest Imperial |
| M1.5 x 0.35 | 1.5 | 0.35 | 1.15 | #56 | 1.60 | #55 | 1.60 | 1/16 | 1.65 | #52 |
| M1.6 x 0.35 | 1.6 | 0.35 | 1.25 | #55 | 1.70 | #54 | 1.70 | #51 | 1.75 | #50 |
| M1.8 x 0.35 | 1.8 | 0.35 | 1.45 | #53 | 1.90 | 1/16 | 1.90 | #49 | 2.00 | 5/64 |
| M2 x 0.45 | 2 | 0.45 | 1.55 | 1/16 | 1.70 | #51 | 2.10 | #45 | 2.20 | #44 |
| M2 x 0.4 | 2 | 0.40 | 1.60 | #52 | 1.75 | #50 | ||||
| M2.2 x 0.45 | 2.2 | 0.45 | 1.75 | #50 | 1.90 | #48 | 2.30 | 3/32 | 2.40 | #41 |
| M2.5 x 0.45 | 2.5 | 0.45 | 2.05 | #46 | 2.65 | #44 | 2.65 | #37 | 2.75 | 7/64 |
| M3 x 0.5 | 3 | 0.5 | 2.50 | #39 | 2.70 | #36 | 3.15 | 1/8 | 3.30 | #30 |
| M3.5 x 0.6 | 3.5 | 0.6 | 2.90 | #32 | 3.10 | #31 | 3.70 | #27 | 3.85 | #24 |
| M4 x 0.75 | 4 | 0.75 | 3.25 | #30 | 3.50 | #28 | 4.20 | #19 | 4.40 | #17 |
| M4 x 0.7 | 4 | 0.7 | 3.30 | #30 | 3.50 | #28 | ||||
| M4.5 x 0.75 | 4.5 | 0.75 | 3.75 | #25 | 4.00 | #22 | 4.75 | #13 | 5.00 | #9 |
| M5 x 1.00 | 5 | 1.0 | 4.00 | #21 | 4.40 | 11/64 | 5.25 | #5 | 5.50 | 7/32 |
| M5 x 0.9 | 5 | 0.9 | 4.10 | #20 | 4.40 | #17 | ||||
| M5 x 0.8 | 5 | 0.8 | 4.20 | #19 | 4.50 | #16 | ||||
| M5.5 x 0.90 | 5.5 | 0.9 | 4.60 | #14 | 4.90 | #10 | 5.80 | #1 | 6.10 | B |
| M6 x 1 | 6 | 1 | 5.00 | #8 | 5.40 | #4 | 6.30 | E | 6.60 | G |
| M6 x 0.75 | 6 | 0.75 | 5.25 | #4 | 5.50 | 7/32 | ||||
| M7 x 1.00 | 7 | 1.00 | 6.00 | B | 6.40 | E | 7.40 | L | 7.70 | N |
| M7 x 0.75 | 7 | 0.75 | 6.25 | D | 6.50 | F | ||||
| M8 x 1.25 | 8 | 1.25 | 6.80 | H | 7.20 | J | 8.40 | Q | 8.80 | S |
| M8 x 1 | 8 | 1 | 7.00 | J | 7.40 | L | ||||
| M9 x 1.25 | 9 | 1.25 | 7.80 | N | 8.20 | P | 9.50 | 3/8 | 9.90 | 25/64 |
| M9 x 1.0 | 9 | 1.0 | 8.00 | O | 8.40 | 21/64 | ||||
| M10 x 1.5 | 10 | 1.5 | 8.50 | R | 9.00 | T | 10.50 | Z | 11.00 | 7/16 |
| M10 x 1.25 | 10 | 1.25 | 8.80 | 11/32 | 9.20 | 23/64 | ||||
| M10 x 1.0 | 10 | 1.00 | 9.00 | T | 9.40 | U | ||||
| M11 x 1.50 | 11 | 1.50 | 9.50 | 3/8 | 10.00 | X | 11.60 | 29/64 | 12.10 | 15/32 |
| M12 x 1.75 | 12 | 1.75 | 10.30 | 13/32 | 10.90 | 27/64 | 12.60 | 1/2 | 13.20 | 33/64 |
| M12 x 1.50 | 12 | 1.50 | 10.50 | Z | 11.00 | 7/16 | ||||
| M12 x 1.25 | 12 | 1.25 | 10.80 | 27/64 | 11.20 | 7/16 | ||||
| M14 x 2 | 14 | 2 | 12.10 | 15/32 | 12.70 | 1/2 | 14.75 | 37/64 | 15.50 | 39/64 |
| M14 x 1.5 | 14 | 1.5 | 12.50 | 1/2 | 13.00 | 33/64 | ||||
| M14 x 1.25 | 14 | 1.25 | 12.80 | 1/2 | 13.2 | 33/64 | ||||
| M16 x 2 | 16 | 2 | 14.00 | 35/64 | 14.75 | 37/64 | 16.75 | 21/32 | 17.50 | 11/16 |
| M16 x 1.5 | 16 | 1.5 | 14.50 | 37/64 | 15.00 | 19/32 | ||||
| M18 x 2.5 | 18 | 2.5 | 15.50 | 39/64 | 16.50 | 41/64 | 19 | 3/4 | 20.00 | 25/32 |
| M18 x 2.0 | 18 | 2.0 | 16.00 | 5/8 | 16.75 | 21/32 | ||||
| M18 x 1.5 | 18 | 1.5 | 16.50 | 21/32 | 17.00 | 43/64 | ||||
| M20 x 2.5 | 20 | 2.5 | 17.50 | 11/16 | 18.50 | 23/32 | 21 | 53/64 | 22.00 | 55/64 |
| M20 x 2.00 | 20 | 2.0 | 18.00 | 45/64 | 18.50 | 46/64 | ||||
| M20 x 1.5 | 20 | 1.5 | 18.50 | 47/64 | 19.00 | 3/4 | ||||
| M22 x 2.5 | 22 | 2.5 | 19.50 | 49/64 | 20.00 | 25/32 | 25 | 1 | 26.00 | 1-1/32 |
| M22 x 1.5 | 22 | 1.5 | 20.50 | 13/16 | 20.75 | 13/16 | ||||
| M24 x 3 | 24 | 3 | 21.88 | 53/64 | 21.50 | 27/32 | 27 | 1-5/64 | 28.00 | 1-7/64 |
| M24 x 2 | 24 | 2 | 22.00 | 7/8 | 22.25 | 7/8 | ||||
| M27 x 3 | 27 | 3 | 24.00 | 15/16 | 24.50 | 31/32 | 30 | 1-3/16 | 32.00 | 1-1/16 |
| M27 x 2 | 27 | 2 | 25.00 | 1 | 25.25 | 1 | ||||
| The values are taken from ... | ||||||||||