# #37 drill size

A #37 drill is 0.1040 in (2.64 mm). It is the standard tap drill for #5-44 UNF; the nearest metric drill is 2.65 mm.

## #37 drill data

- Series: Number drill
- Decimal: 0.1040 in
- Metric: 2.64 mm (2.6416 mm exact)
- Nearest metric drill: 2.65 mm (+0.008 mm)
- Nearest fractional: 7/64" (0.1094 in)
- Standard tap drill for: #5-44 UNF

## Nearest metric drills

| Metric drill | Inch | Difference |
|---|---|---|
| 2.6 mm | 0.1024 | −0.042 mm |
| 2.65 mm | 0.1043 | +0.008 mm |

## Nearby inch drills

| Drill | Series | Inch | mm |
|---|---|---|---|
| 3/32" | Fractional | 0.0938 | 2.38 |
| #38 | Number | 0.1015 | 2.58 |
| #37 | Number | 0.1040 | 2.64 |
| #36 | Number | 0.1065 | 2.71 |
| 7/64" | Fractional | 0.1094 | 2.78 |
| Letter A | Letter | 0.2340 | 5.94 |

## Threads this drill can tap

| Thread | Standard drill | Thread % with this drill |
|---|---|---|
| #5-44 UNF | #37 | 71 |
| M3 × 0.35 | 2.65 mm | 79 |
| #6-32 UNC | #36 | 84 |
| #5-40 UNC | #38 | 65 |
| M3 × 0.5 | 2.5 mm | 55 |

## Clearance

| Fastener | Diameter | Clearance | Per side | ISO 273 |
|---|---|---|---|---|
| #1 screw | 0.0730" | 0.0310" | 0.0155" | – |
| #2 screw | 0.0860" | 0.0180" | 0.0090" | – |
| M2.5 bolt | 2.5 mm | 0.14 mm | 0.07 mm | Tighter than close fit (2.7 mm) |
| #3 screw | 0.0990" | 0.0050" | 0.0025" | – |


## FAQ

**What size is a #37 drill?**
A #37 drill is 0.1040 in, which is 2.64 mm (2.6416 mm exactly).

**What is the metric equivalent of a #37 drill?**
The nearest metric drill is 2.65 mm, 0.008 mm larger. The other close size is 2.6 mm.

**What tap uses a #37 drill?**
A #37 drill is the standard tap drill for #5-44 UNF (about 71 % thread).

**Which fractional drill is closest to #37?**
7/64 in (0.1094 in) is the closest, 0.0054 in larger.

**What does a #37 drill clear?**
It clears a #3 screw with 0.0050" total clearance (0.0025" per side).

Source page: https://machinistcharts.com/drill-size/number-37/
Updated: 2026-10-06
Publisher: MachinistCharts (https://machinistcharts.com)