59/64" drill size
A 59/64 in drill is 0.9219 in (23.42 mm). It is the standard tap drill for 1-12 UNF; the nearest metric drill is 23.4 mm.
59/64" at a glance
Decimal, metric and the nearest sizes in the other series.
Nearest metric drills
Metric drills step by 0.05 mm below 3 mm and by 0.1 mm from 3 mm. Difference is metric minus inch size.
| Metric drill | Inch | Difference | In inches | Hole |
|---|---|---|---|---|
| 23.4 mm | 0.9213" | −0.016 mm | −0.0006" | Smaller |
| 23.5 mm | 0.9252" | +0.084 mm | +0.0033" | Larger |
Nearby inch drills
The next size down and up in each inch series, so you can pick a substitute from the drawer.
Threads a 59/64" drill can tap
Threads from the tap tables on this site that this drill can tap, with the thread percentage it leaves (55–85 % shown).
Clearance for screws and bolts
Bolts and screws a 59/64" hole clears, with the diametral clearance and the gap each side. Metric sizes are compared with ISO 273.
| Fastener | Diameter | Clearance | Per side | ISO 273, metric only |
|---|---|---|---|---|
| M20 bolt | 20 mm | 3.42 mm | 1.71 mm | Normal fit (normal 22, loose 24 mm) |
| M22 bolt | 22 mm | 1.42 mm | 0.71 mm | Close fit (close 23, normal 24 mm) |
| 7/8" bolt | 0.8750" | 0.0469" | 0.0234" | – |
Inch clearance is the drill size minus the basic major diameter. A drilled hole usually cuts slightly oversize.
Fractional drill index
Every size in the series, holes drawn to scale.
Common questions
What size is a 59/64 in drill?
A 59/64 in drill is 0.9219 in, which is 23.42 mm (23.4156 mm exactly).
What is the metric equivalent of a 59/64 in drill?
The nearest metric drill is 23.4 mm, 0.016 mm smaller. The other close size is 23.5 mm.
What tap uses a 59/64 in drill?
A 59/64 in drill is the standard tap drill for 1-12 UNF (about 72 % thread).
What does a 59/64 in drill clear?
It clears a 7/8" bolt with 0.0469" total clearance (0.0234" per side).