#13 Drill Size: 0.185 in / 4.7 mm

What a #13 drill taps

Every thread this drill cuts between 50% and 85% of thread, deepest first. Outside that band it is the wrong drill for the job, so nothing below that line is listed.

Threads a #13 drill taps, with the percent of thread each one gets and the published chart drill for comparison.
Thread	% thread	Chart drill	Chart %
#12-32 chart drill	76.4%	#13	76.4%
#12-28	66.8%	#14	73.3%
#12-24	57.3%	#16	72.1%

Other jobs for a #13

Hard-material tap drill: The size to use in stainless or tool steel for #12-24, where it leaves a shallower thread than the standard drill and cuts tapping torque.
Clearance hole: The through hole a bolt passes in, not a tapped hole: loose fit for #6-32, loose fit for #6-40. See the clearance hole chart.

Drills either side

All drill sizes → · Open this drill in the calculator →

#13 drill: common questions

What size is a #13 drill?

0.185 inches, which is 4.70 mm. It is a number drill.

What can I tap with a #13 drill?

3 threads: #12-32 at 76.4%, #12-28 at 66.8%, #12-24 at 57.3%.

Is a #13 drill the standard tap drill for anything?

Yes, for #12-32 (76.4% thread). That is the size published tap and drill charts give.

Is a #13 drill used for clearance holes?

Yes: loose fit for #6-32, loose fit for #6-40. A clearance hole is not tapped; the bolt passes through it.

What drill is next to a #13?

Down: #14 at 0.182 in. Up: 4.7 mm at 0.185 in.