#37 drill size
A #37 drill is 0.1040 in (2.64 mm). It is the standard tap drill for #5-44 UNF; the nearest metric drill is 2.65 mm.
#37 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 |
|---|---|---|---|---|
| 2.6 mm | 0.1024" | −0.042 mm | −0.0016" | Smaller |
| 2.65 mm | 0.1043" | +0.008 mm | +0.0003" | 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 #37 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 #37 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 |
|---|---|---|---|---|
| #1 screw | 0.0730" | 0.0310" | 0.0155" | – |
| #2 screw | 0.0860" | 0.0180" | 0.0090" | – |
| M2.5 bolt | 2.5 mm | 0.14 mm | 0.07 mm | Tighter than close fit (2.7 mm) |
| #3 screw | 0.0990" | 0.0050" | 0.0025" | – |
Inch clearance is the drill size minus the basic major diameter. A drilled hole usually cuts slightly oversize.
Number drill index
Every size in the series, holes drawn to scale.
Common questions
What size is a #37 drill?
A #37 drill is 0.1040 in, which is 2.64 mm (2.6416 mm exactly).
What is the metric equivalent of a #37 drill?
The nearest metric drill is 2.65 mm, 0.008 mm larger. The other close size is 2.6 mm.
What tap uses a #37 drill?
A #37 drill is the standard tap drill for #5-44 UNF (about 71 % thread).
Which fractional drill is closest to #37?
7/64 in (0.1094 in) is the closest, 0.0054 in larger.
What does a #37 drill clear?
It clears a #3 screw with 0.0050" total clearance (0.0025" per side).