#34 drill bit size
0.111 in
2.82 mm · number drill
| Inches | 0.111 in |
| Millimetres | 2.82 mm |
| Nearest metric drill | 2.8 mm |
| System | Number (#1 to #60) |
What #34 means
A bit marked #34 is a number drill, and the number is an index rather than a measurement — the higher the number, the smaller the bit. #1 is 0.228 inches and #60 is 0.04. That is the opposite of the fractional sizes stamped on a home set, which is why a number drill and a fraction of similar appearance can be very different holes.
The same hole in the other systems
Three drill systems overlap across this range and a workshop rarely has all three. The nearest bit of each other kind to #34:
| System | Nearest size | Difference |
|---|---|---|
| letter | A — 0.234 in | 0.123 in larger |
| fractional | 7/64" — 0.1094 in | 0.0016 in smaller |
| metric | 2.8 mm | 0.019 mm smaller |
One of those is within three thousandths of an inch, which is inside the tolerance of most hand-held work — substitute it and nobody will know.
What gets drilled at 0.111 inches
The busiest part of the number series. Tapping drills for machine screws from #4 to #12 sit in here, along with pilot holes for wood screws and clearance for small pins. If a number drill in a workshop is worn out, it is usually one of these.
Either side of it
| Drill | Inches | Millimetres |
|---|---|---|
| #36 | 0.1065 in | 2.71 mm |
| 7/64" | 0.1094 in | 2.78 mm |
| #35 | 0.11 in | 2.79 mm |
| #34 | 0.111 in | 2.82 mm |
| #33 | 0.113 in | 2.87 mm |
| #32 | 0.116 in | 2.95 mm |
| #31 | 0.12 in | 3.05 mm |
Frequently asked questions
What size is a #34 drill bit?
0.111 inches, which is 2.82 mm. Number drills run from #1 at 0.228 inches down to #60 at 0.04, getting smaller as the number rises — the opposite of what most people expect the first time.
What is a #34 drill bit in mm?
2.82 mm. A metric index will offer 2.8 mm as the nearest stocked size, which is near enough identical.
Is #34 a tapping drill size?
Not for any of the unified threads on this site. The next size up, #33, is the tapping drill for 6-40.
What is the next size up from #34?
#33 at 0.113 inches — 0.002 inches larger. Below it is #35 at 0.11.
Other sizes
- #33 drill bit — 0.113 in, 2.87 mm
- #32 drill bit — 0.116 in, 2.95 mm
- #31 drill bit — 0.12 in, 3.05 mm
- 1/8" drill bit — 0.125 in, 3.18 mm
- #30 drill bit — 0.1285 in, 3.26 mm
- #29 drill bit — 0.136 in, 3.45 mm
- #28 drill bit — 0.1405 in, 3.57 mm
- 9/64" drill bit — 0.1406 in, 3.57 mm