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#1 drill bit size
#1 drill = .2280 in = 5.79 mm. Closest metric drill: 5.8 mm.
Nearby drill sizes
| Drill | Type | Inch | mm | Difference |
|---|---|---|---|---|
| #4 | number | .2090 in | 5.309 | -19.0 thou |
| #3 | number | .2130 in | 5.410 | -15.0 thou |
| 7/32 | fraction | .2188 in | 5.556 | -9.3 thou |
| #2 | number | .2210 in | 5.613 | -7.0 thou |
| #1 | number | .2280 in | 5.791 | 0.0 thou |
| A | letter | .2340 in | 5.944 | 6.0 thou |
| 15/64 | fraction | .2344 in | 5.953 | 6.4 thou |
| B | letter | .2380 in | 6.045 | 10.0 thou |
| C | letter | .2420 in | 6.147 | 14.0 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.