#21 Drill Size
A #21 number drill is 0.1590" (4.039 mm).
Closest fraction: 5/32 (0.1562", under by 0.0028").
Tap drill for
Next size down / up
| Drill | Inch | mm |
|---|---|---|
| 4 mm | 0.1575 | 4.000 |
| #20 | 0.1610 | 4.089 |
Printable PDF version - Drill Size Chart
Clean letter-size sheet for the toolbox or shop wall. Instant download, $3.49.
Clean letter-size sheet for the toolbox or shop wall. Instant download, $3.49.