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#40 drill bit size
#40 drill = .0980 in = 2.49 mm. Closest metric drill: 2.5 mm.
Nearby drill sizes
| Drill | Type | Inch | mm | Difference |
|---|---|---|---|---|
| #43 | number | .0890 in | 2.261 | -9.0 thou |
| #42 | number | .0935 in | 2.375 | -4.5 thou |
| 3/32 | fraction | .0938 in | 2.381 | -4.3 thou |
| #41 | number | .0960 in | 2.438 | -2.0 thou |
| #40 | number | .0980 in | 2.489 | 0.0 thou |
| #39 | number | .0995 in | 2.527 | 1.5 thou |
| #38 | number | .1015 in | 2.578 | 3.5 thou |
| #37 | number | .1040 in | 2.642 | 6.0 thou |
| #36 | number | .1065 in | 2.705 | 8.5 thou |
1 thou = 0.001 in = 0.0254 mm. Drills a few thou apart are usually interchangeable for clearance holes, but not for tap drills or reamer pilots.