# #9 drill size

A #9 drill is 0.1960 in (4.98 mm). It sits between #10 and #8 in the number series; the nearest metric drill is 5.0 mm.

## #9 drill data

- Series: Number drill
- Decimal: 0.1960 in
- Metric: 4.98 mm (4.9784 mm exact)
- Nearest metric drill: 5.0 mm (+0.022 mm)
- Nearest fractional: 13/64" (0.2031 in)

## Nearest metric drills

| Metric drill | Inch | Difference |
|---|---|---|
| 4.9 mm | 0.1929 | −0.078 mm |
| 5.0 mm | 0.1969 | +0.022 mm |

## Nearby inch drills

| Drill | Series | Inch | mm |
|---|---|---|---|
| 3/16" | Fractional | 0.1875 | 4.76 |
| #10 | Number | 0.1935 | 4.91 |
| #9 | Number | 0.1960 | 4.98 |
| #8 | Number | 0.1990 | 5.05 |
| 13/64" | Fractional | 0.2031 | 5.16 |
| Letter A | Letter | 0.2340 | 5.94 |

## Threads this drill can tap

| Thread | Standard drill | Thread % with this drill |
|---|---|---|
| M6 × 1 | 5 mm | 79 |
| 1/4-20 UNC | #7 | 83 |

## Clearance

| Fastener | Diameter | Clearance | Per side | ISO 273 |
|---|---|---|---|---|
| #6 screw | 0.1380" | 0.0580" | 0.0290" | – |
| #8 screw | 0.1640" | 0.0320" | 0.0160" | – |
| #10 screw | 0.1900" | 0.0060" | 0.0030" | – |


## FAQ

**What size is a #9 drill?**
A #9 drill is 0.1960 in, which is 4.98 mm (4.9784 mm exactly).

**What is the metric equivalent of a #9 drill?**
The nearest metric drill is 5.0 mm, 0.022 mm larger. The other close size is 4.9 mm.

**What thread can I tap with a #9 drill?**
It leaves about 79 % thread in M6 × 1 and 83 % in 1/4-20 UNC.

**Which fractional drill is closest to #9?**
13/64 in (0.2031 in) is the closest, 0.0071 in larger.

**What does a #9 drill clear?**
It clears a #10 screw with 0.0060" total clearance (0.0030" per side).

Source page: https://machinistcharts.com/drill-size/number-9/
Updated: 2026-10-06
Publisher: MachinistCharts (https://machinistcharts.com)