5/8-11 UNC tap drill size

17/32 drill — 0.5313 in / 13.49 mm (79% thread)

Major Ø 0.6250 in · 11 threads per inch · coarse series. The chart pick targets 75% thread; nearby standard drills:

Drill	Decimal (in)	mm	Thread %
9/16	0.5625	14.29	53%
35/64	0.5469	13.89	66%
17/32	0.5313	13.49	79%
33/64	0.5156	13.10	93%

Cut taps only — roll-form taps need a larger hole. 65–75% suits general work; drop toward 55% in tough material. Verify before you cut.

Same size, fine series: 5/8-18 UNF