33/64 in Drill Size

fractional drill

33/64″ 0.5156 in 13.10 mm

A 33/64 in drill is the standard tap drill for 9/16-18 and 9/16-24.

What a 33/64 in 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 33/64 in drill taps, with the percent of thread each one gets and the published chart drill for comparison.
Thread	% thread	Chart drill	Chart %
9/16-18 chart drill	65.0%	33/64″	65.0%
M14 x 1.25	55.6%	12.8 mm	73.9%

Drills either side

13 mm 0.5118 in · 13 mm Next size down
13.1 mm 0.5157 in · 13.1 mm Next size up

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

33/64 in drill: common questions

What size is a 33/64 in drill?

0.5156 inches, which is 13.10 mm. It is a fractional drill.

What can I tap with a 33/64 in drill?

2 threads: 9/16-18 at 65.0%, M14 x 1.25 at 55.6%.

Is a 33/64 in drill the standard tap drill for anything?

Yes, for 9/16-18 (65.0% thread) and 9/16-24 (86.6% thread). That is the size published tap and drill charts give.

What drill is next to a 33/64 in?

Down: 13 mm at 0.5118 in. Up: 13.1 mm at 0.5157 in.