#15 Drill Size

number drill

#15 0.180 in 4.57 mm

A #15 drill measures 0.180 in. It taps 2 threads in this chart.

What a #15 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 #15 drill taps, with the percent of thread each one gets and the published chart drill for comparison.
Thread	% thread	Chart drill	Chart %
#12-28	77.6%	#14	73.3%
#12-24	66.5%	#16	72.1%

Other jobs for a #15

Clearance hole: The through hole a bolt passes in, not a tapped hole: close fit for #8-32, close fit for #8-36. See the clearance hole chart.

Drills either side

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#15 drill: common questions

What size is a #15 drill?

0.180 inches, which is 4.57 mm. It is a number drill.

What can I tap with a #15 drill?

2 threads: #12-28 at 77.6%, #12-24 at 66.5%.

Is a #15 drill used for clearance holes?

Yes: close fit for #8-32, close fit for #8-36. A clearance hole is not tapped; the bolt passes through it.

What drill is next to a #15?

Down: 4.5 mm at 0.1772 in. Up: 4.6 mm at 0.1811 in.