39/64" drill size
A 39/64 in drill is 0.6094 in (15.48 mm). It sits between 19/32 in and 5/8 in in the fractional series; the nearest metric drill is 15.5 mm.
39/64" 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 |
|---|---|---|---|---|
| 15.4 mm | 0.6063" | −0.078 mm | −0.0031" | Smaller |
| 15.5 mm | 0.6102" | +0.022 mm | +0.0009" | 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 39/64" 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).
| Thread | Standard drill | Thread with this drill | Suits |
|---|---|---|---|
| M18 × 2.5 | 15.5 mm | 78 % | Soft metals, plastics |
Clearance for screws and bolts
Bolts and screws a 39/64" 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 |
|---|---|---|---|---|
| M14 bolt | 14 mm | 1.48 mm | 0.74 mm | Close fit (close 15, normal 15.5 mm) |
| 9/16" bolt | 0.5625" | 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 39/64 in drill?
A 39/64 in drill is 0.6094 in, which is 15.48 mm (15.4781 mm exactly).
What is the metric equivalent of a 39/64 in drill?
The nearest metric drill is 15.5 mm, 0.022 mm larger. The other close size is 15.4 mm.
What thread can I tap with a 39/64 in drill?
It leaves about 78 % thread in M18 × 2.5.
What does a 39/64 in drill clear?
It clears a 9/16" bolt with 0.0469" total clearance (0.0234" per side).