UNF Thread ANSI B1.1

UNF Thread ANSI B1.1

UNF - Unified National Fine Thread. Similar to UNC. UNC and UNF threads are the choices for the customary screws and nuts.

Nominal Diameter	Major Diameter Inch	Major Diameter mm	Tapping Drill Size mm	TPI	Pitch mm
N 0 - 80 UNF	0,060	1,524	1,25	80	0,317
N 1 - 72 UNF	0,073	1,854	1,55	72	0,353
N 2 - 64 UNF	0,068	2,184	1,90	64	0,397
N 3 - 56 UNF	0,099	2,515	2,15	56	0,453
N 4 - 48 UNF	0,112	2,845	2,40	48	0,529
N 5 - 44 UNF	0,125	3,175	2,70	44	0,577
N 6 - 40 UNF	0,138	3,505	2,95	40	0,635
N 8 - 36 UNF	0,164	4,166	3,50	36	0,705
N 10 - 32 UNF	0,190	4,826	4,10	32	0,794
N 12 - 28 UNF	0,216	5,486	4,70	28	0,907
1/4" - 28 UNF	0,250	6,350	5,50	28	0,907
5/16" - 24 UNF	0,313	7,938	6,90	24	1,058
3/8" - 24 UNF	0,375	9,525	8,50	24	1,058
7/16" - 20 UNF	0,438	11,112	9,90	20	1,270
1/2" - 20 UNF	0,500	12,700	11,50	20	1,270
9/16" - 18 UNF	0,563	14,288	12,90	18	1,411
5/8" - 18 UNF	0,625	15,875	14,50	18	1,411
3/4" - 16 UNF	0,750	19,050	17,50	16	1,587
7/8" - 14 UNF	0,875	22,225	20,40	14	1,814
1" - 12 UNF	1,000	25,400	23,25	12	2,117
1 1/8" - 12 UNF	1,125	28,575	26,50	12	2,117
1 1/4" - 12 UNF	1,250	31,750	29,50	12	2,117
1 3/8" - 12 UNF	1,375	34,925	32,75	12	2,117
1 1/2" - 12 UNF	1,500	38,100	36,00	12	2,117