Thread Diameter	Basic Major Diameter	Basic Pitch Diameter	Thread Diameter	Basic Major Diameter	Basic Pitch Diameter
2/56	0.0860	0.0744	9/16-18	0.5625	0.5264
2/64	0.0860	0.0759	5/8-11	0.6250	0.5660
3/48	0.0990	0.0855	5/8-18	0.6250	0.5889
3/56	0.0990	0.0874	3/4-10	0.7500	0.6850
4/40	0.1120	0.0958	3/4-16	0.7500	0.7094
4/48	0.1120	0.0985	7/8-9	0.8750	0.8028
5/40	0.1250	0.1088	7/8-14	0.8750	0.8286
5/44	0.1250	0.1102	1-8	1.0000	0.9188
6/32	0.1380	0.1177	1-12	1.0000	0.9459
6/40	0.1380	0.1218	1-1/8-7	1.1250	1.0322
8/32	0.1640	0.1437	1-1/8-12	1.1250	1.0709
8/36	0.1640	0.1460	1-1/4-7	1.2500	1.1572
10/24	0.1900	0.1629	1-1/4-12	1.2500	1.1959
10/32	0.1900	0.1697	1-3/8-6	1.3750	1.2667
12/24	0.2160	0.1889	1-3/8-12	1.3750	1.3209
12/28	0.2160	0.1928	1-1/2-6	1.5000	1.3917
1/4-20	0.2500	0.2175	1-1/2-12	1.5000	1.4459
1/4-28	0.2500	0.2268	1-3/4-5	1.7500	1.6201
5/16-18	0.3125	0.2764	2-4-1/2	2.0000	1.8557
5/16-24	0.3125	0.2854	2-1/4-4-1/2	2.2500	2.1057
3/8-16	0.3750	0.3344	2-1/2-4	2.5000	2.3376
3/8-24	0.3750	0.3479	2-3/4-4	2.7500	2.5876
7/16-14	0.4375	0.3911	3-4	3.0000	2.8376
7/16-20	0.4375	0.4050	3-1/4-4	3.2500	3.0876
1/2-13	0.5000	0.4500	3-1/2-4	3.5000	3.3376
1/2-20	0.5000	0.4675	3-3/4-4	3.7500	3.5876
9/16-12	0.5625	0.5084	4-4	4.0000	3.8376