41/64" drill size
A 41/64 in drill is 0.6406 in (16.27 mm). It sits between 5/8 in and 21/32 in in the fractional series; the nearest metric drill is 16.3 mm.
41/64" 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 |
|---|---|---|---|---|
| 16.2 mm | 0.6378" | −0.072 mm | −0.0028" | Smaller |
| 16.3 mm | 0.6417" | +0.028 mm | +0.0011" | 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 41/64" 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 |
|---|---|---|---|
| 3/4-10 UNC | 21/32 | 84 % | Soft metals, plastics |
Clearance for screws and bolts
Bolts and screws a 41/64" 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 | 2.27 mm | 1.14 mm | Normal fit (normal 15.5, loose 16.5 mm) |
| 5/8" bolt | 0.6250" | 0.0156" | 0.0078" | – |
| M16 bolt | 16 mm | 0.27 mm | 0.14 mm | Tighter than close fit (17 mm) |
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 41/64 in drill?
A 41/64 in drill is 0.6406 in, which is 16.27 mm (16.2719 mm exactly).
What is the metric equivalent of a 41/64 in drill?
The nearest metric drill is 16.3 mm, 0.028 mm larger. The other close size is 16.2 mm.
What thread can I tap with a 41/64 in drill?
It leaves about 84 % thread in 3/4-10 UNC.
What does a 41/64 in drill clear?
It clears a M16 bolt with 0.27 mm total clearance (0.14 mm per side); for metric bolts: tighter than close fit.