#9 drill size
A #9 drill is 0.1960 in (4.98 mm). It sits between #10 and #8 in the number series; the nearest metric drill is 5.0 mm.
#9 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 |
|---|---|---|---|---|
| 4.9 mm | 0.1929" | −0.078 mm | −0.0031" | Smaller |
| 5.0 mm | 0.1969" | +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 #9 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 |
|---|---|---|---|
| M6 × 1 | 5 mm | 79 % | Soft metals, plastics |
| 1/4-20 UNC | #7 | 83 % | Soft metals, plastics |
Clearance for screws and bolts
Bolts and screws a #9 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 |
|---|---|---|---|---|
| #6 screw | 0.1380" | 0.0580" | 0.0290" | – |
| #8 screw | 0.1640" | 0.0320" | 0.0160" | – |
| #10 screw | 0.1900" | 0.0060" | 0.0030" | – |
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 #9 drill?
A #9 drill is 0.1960 in, which is 4.98 mm (4.9784 mm exactly).
What is the metric equivalent of a #9 drill?
The nearest metric drill is 5.0 mm, 0.022 mm larger. The other close size is 4.9 mm.
What thread can I tap with a #9 drill?
It leaves about 79 % thread in M6 × 1 and 83 % in 1/4-20 UNC.
Which fractional drill is closest to #9?
13/64 in (0.2031 in) is the closest, 0.0071 in larger.
What does a #9 drill clear?
It clears a #10 screw with 0.0060" total clearance (0.0030" per side).