# M24x2 tap drill size

The tap drill for an M24 × 2 metric fine thread is 22 mm (0.8661 in). It leaves about 77 % thread, the normal range for steel.

## Drill options for M24 × 2

| Drill | Inch | Thread % |
|---|---|---|
| 21.8 mm | 0.8583 | 85 % |
| 21.9 mm | 0.8622 | 81 % |
| 22 mm | 0.8661 | 77 % |
| 22.1 mm | 0.8701 | 73 % |
| 22.2 mm | 0.8740 | 69 % |

## M24x2 thread data

- Thread: M24 × 2 (fine)
- Pitch: 2 mm
- Tap drill: 22 mm (0.8661 in)
- Thread engagement: 77 %
- Clearance hole (ISO 273): 25 close, 26 normal, 28 loose (mm)

## Method

Thread % = 76.98 × (D − drill) / P = 76.98 × 2 / 2 = 77 %. Aim for 65–75 % in steel, 75–85 % in aluminium, brass and plastics.

## FAQ

**What size drill for an M24 × 2 tap?**
Use a 22 mm drill. It leaves about 77 % thread engagement.

**What is 22 mm in inches?**
22 mm is 0.8661 inch.

**What size clearance hole for M24?**
ISO 273 gives 25 mm for a close fit, 26 mm normal and 28 mm loose.

**How tight should an M24 bolt be?**
About 761 N·m for class 8.8 with dry threads.

Source page: https://machinistcharts.com/tap-drill/m24x2/
Updated: 2026-10-05
Publisher: MachinistCharts (https://machinistcharts.com)