---
type: "drill"
designation: "1.15 mm"
series: "metric"
series_name: "Metric Drill Sizes"
diameter_in: 0.045276
diameter_mm: 1.15
standard: "ANSI/ASME B94.11M; BS 328"
verified: "August 1, 2026"
url: https://shopmath.org/drills/metric/1-15mm
---

# 1.15 mm Drill Bit Size — 0.0453 in / 1.150 mm

A 1.15 mm drill bit is 0.0453 in (1.150 mm) in diameter. It belongs to the metric series of standard twist drills.

- **Designation**: 1.15 mm
- **Series**: Metric
- **Diameter**: 0.0453 in (1.150 mm)

## 1.15 mm Drill Diameter

| Property | Value |
| --- | --- |
| Designation | 1.15 mm |
| Series | Metric |
| Diameter (in) | 0.0453 |
| Diameter (mm) | 1.150 |

## 1.15 mm Drill Equivalents in the Other Size Series

The nearest standard drill to 1.15 mm in each of the other three series. Nothing here is an exact match unless the difference column reads 0.0000 in.

| Series | Nearest drill | Diameter (in) | Diameter (mm) | Difference |
| --- | --- | --- | --- | --- |
| Number | [#56](https://shopmath.org/drills/number/56.md) | 0.0465 | 1.181 | +0.0012 in |
| Letter | [A](https://shopmath.org/drills/letter/a.md) | 0.2340 | 5.944 | +0.1887 in |
| Fractional | [3/64](https://shopmath.org/drills/fractional/3-64.md) | 0.0469 | 1.191 | +0.0016 in |

## Sources and Method for the 1.15 mm Drill Size

### Drill index

- **Source**: Number/letter: bd_warehouse drill_sizes.csv (Apache-2.0) cross-checked against Wikipedia Drill bit sizes (CC BY-SA 4.0). Fractional: computed 1/64 in steps per ANSI B94.11M. Metric: computed BS 328 increment pattern.
- **Method**: computed
- **Verified against**: Wikipedia Drill bit sizes (CC BY-SA 4.0); 31/31 checks passed

### Assumptions

- Drill diameters are nominal. A worn or run-out drill cuts oversize; measure the hole, not the shank, when the fit matters.
- Dataset scope: Number sizes #61-#80 are stored but tagged demandTier 'extended' — query-space-map.md Appendix A found the tail thinning in the 60s. Sizes below #80 and metric sizes above 25.0 mm excluded.

**Data last verified**: August 1, 2026

## Common Questions About the 1.15 mm Drill Bit

### What size is a 1.15 mm drill bit size?

A 1.15 mm drill bit is 0.0453 in (1.150 mm) in diameter.

### What fraction is a 1.15 mm drill bit?

1.15 mm is 0.0453 in (1.150 mm), which is not itself a fractional size. The closest fractional drill is 3/64 at 0.0469 in (1.191 mm).

## Related pages

- Next size down (any series): [1.1 mm](https://shopmath.org/drills/metric/1-1mm.md) — 0.0433 in (1.100 mm)
- Next size up (any series): [#56](https://shopmath.org/drills/number/56.md) — 0.0465 in (1.181 mm)
- Previous in the metric series: [1.1 mm](https://shopmath.org/drills/metric/1-1mm.md)
- Next in the metric series: [1.2 mm](https://shopmath.org/drills/metric/1-2mm.md)
- All metric sizes: [Metric drill sizes](https://shopmath.org/drills/metric.md)
- All drill sizes: [Drill bit size reference](https://shopmath.org/drills.md)
- Complete index by diameter: [Drill size chart](https://shopmath.org/charts/drill-sizes.md)
- Tap drills by thread: [Tap drill chart](https://shopmath.org/charts/tap-drill.md)

---

*Source: [ShopMath](https://shopmath.org/drills/metric/1-15mm) — data verified August 1, 2026. Reference data; verify against the governing standard before manufacture.*