Thread Table

Use our thread table to look up the pitch and threads-per-inch for the most common screw sizes.

PITCH (MM)						THREADS PER INCH (TPI)
	Size		Coarse	Fine	Extra Fine	UNC	UNF	BSW	BSF
M1.6	-	#0	0.35	-	-	-	80	-	-
M2	-	#1	0.4	-	-	-	72	-	-
-	-	#2	-	-	-	56	64	-	-
M2.5	-	#3	0.45	-	-	48	56	-	-
-	-	#4	-	-	-	40	48	-	-
M3	1/8"	#5	0.5	-	-	40	44	40	-
M3.5	-	#6	0.6	-	-	32	40	-	-
M4	-	#8	0.7	-	-	32	36	-	-
M5	3/16"	#10	0.8	-	-	24	32	24	32
-	-	#12	-	-	-	24	28	-	-
M6	1/4"	-	1	-	-	20	28	20	26
M8	5/16"	-	1.25	1	-	18	24	18	22
M10	3/8"	-	1.5	1.25	1	16	24	16	20
-	7/16"	-	-	-	-	14	20	14	18
M12	1/2"	-	1.75	1.5	1.25	13	20	12	16
M14	9/16"	-	2	1.5	-	12	18	12	16
M16	5/8"	-	2	1.5	-	11	18	11	14
M18	-	-	2.5	1.5	-	-	-	-	-
M20	3/4"	-	2.5	1.5	-	10	16	10	12
M22	7/8"	-	2.5	1.5	-	9	14	9	11
M24	1"	-	3	2	-	8	12 (14)	8	10