# #46 drill size

A #46 drill is 0.0810 in (2.06 mm). It sits between #47 and #45 in the number series; the nearest metric drill is 2.05 mm.

## #46 drill data

- Series: Number drill
- Decimal: 0.0810 in
- Metric: 2.06 mm (2.0574 mm exact)
- Nearest metric drill: 2.05 mm (−0.007 mm)
- Nearest fractional: 5/64" (0.0781 in)

## Nearest metric drills

| Metric drill | Inch | Difference |
|---|---|---|
| 2.05 mm | 0.0807 | −0.007 mm |
| 2.1 mm | 0.0827 | +0.043 mm |

## Nearby inch drills

| Drill | Series | Inch | mm |
|---|---|---|---|
| 5/64" | Fractional | 0.0781 | 1.98 |
| #47 | Number | 0.0785 | 1.99 |
| #46 | Number | 0.0810 | 2.06 |
| #45 | Number | 0.0820 | 2.08 |
| 3/32" | Fractional | 0.0938 | 2.38 |
| Letter A | Letter | 0.2340 | 5.94 |

## Threads this drill can tap

| Thread | Standard drill | Thread % with this drill |
|---|---|---|
| M2.5 × 0.45 | 2.05 mm | 76 |
| #3-56 UNF | #45 | 78 |
| #3-48 UNC | #47 | 67 |

## Clearance

| Fastener | Diameter | Clearance | Per side | ISO 273 |
|---|---|---|---|---|
| #1 screw | 0.0730" | 0.0080" | 0.0040" | – |
| M2 bolt | 2 mm | 0.06 mm | 0.03 mm | Tighter than close fit (2.2 mm) |


## FAQ

**What size is a #46 drill?**
A #46 drill is 0.0810 in, which is 2.06 mm (2.0574 mm exactly).

**What is the metric equivalent of a #46 drill?**
The nearest metric drill is 2.05 mm, 0.007 mm smaller. The other close size is 2.1 mm.

**What thread can I tap with a #46 drill?**
It leaves about 76 % thread in M2.5 × 0.45 and 78 % in #3-56 UNF.

**Which fractional drill is closest to #46?**
5/64 in (0.0781 in) is the closest, 0.0029 in smaller.

**What does a #46 drill clear?**
It clears a M2 bolt with 0.06 mm total clearance (0.03 mm per side); for metric bolts: tighter than close fit.

Source page: https://machinistcharts.com/drill-size/number-46/
Updated: 2026-10-06
Publisher: MachinistCharts (https://machinistcharts.com)