Simple Drill and Tap Chart - INCH

Every tool site has a Drill and Tap Chart. They are stuffed with lots of useless information and are often so small you need a magnifying glass to read them. Here is a simple and concise version that should be useful on a phone or tablet. These tables are for National Thread, Imperial (inch) organized by Course, Fine and finally Pipe threads. Your eyes will thanks me later! If you need a size not listed better hit up Google!

Looking for other Tap and Drill Guides?

Click for the Metric Tap and Drill Chart

Click for the British Tap and Drill Chart

Tap and Drill Chart - National Coarse Threads Inch
Thread	Drill Size	Decimal Equivalent
#4-40	43	0.0890
#6-32	36	0.1065
#8-32	29	0.1360
#10-24	25	0.1495
#12-24	16	0.1770
1/4-20	7	0.2010
5/16-18	F	0.2570
3/8-16	5/16	0.3125
7/16-14	U	0.3680
1/2-13	27/64	0.4219
9/16-12	31/64	0.4844
5/8-11	17/32	0.5312
3/4-10	21/32	0.6562
7/8-9	49/64	0.7656
1-8	7/8	0.8750

Tap and Drill Chart - National Fine Threads Inch
Thread	Drill Size	Decimal Equivalent
#4-48	42	0.0935
#6-40	33	0.1130
#8-36	29	0.1360
#10-32	21	0.1590
#12-28	14	0.1820
1/4-28	3	0.2130
5/16-24	I	0.2720
3/8-24	Q	0.3320
7/16-20	25/64	0.3906
1/2-20	29/64	0.4531
9/16-18	33/64	0.5156
5/8-18	37/64	0.5781
3/4-16	11/16	0.6875
7/8-14	13/16	0.8125
1-12	15/16	0.9375

Tap and Drill Chart - Tapered Pipe Threads (NPT) Inch
Thread	Drill Size	Decimal Equivalent
1/16-27	D	0.2460
1/8-27	R	0.3390
1/4-18	7/16	0.4375
3/8-18	37/64	0.5781
1/2-14	23/32	0.7187
3/4-14	59/64	0.9219
1-11.5	1-5/32	1.1562