ISO Metric Coarse – Solid Fluid

Nominal Diameter	Pitch	Basic Major Diameter	Basic Effective Diameter	Basic Minor Diameter of External Threads	Basic Minor Diameter of Internal Threads	Tapping Drill	Clearance Drill
(mm)	(mm)	(mm)	(mm)	(mm)	(mm)	(mm)	(mm)
1	0.25	1	0.838	0.693	0.729	0.75	1.05
1.1	0.25	1.1	0.938	0.793	0.829	0.85	1.15
1.2	0.25	1.2	1.038	0.893	0.929	0.95	1.25
1.4	0.3	1.4	1.205	1.032	1.075	1.1	1.45
1.6	0.35	1.6	1.373	1.17	1.221	1.25	1.65
1.8	0.35	1.8	1.573	1.37	1.421	1.45	1.85
2	0.4	2	1.74	1.509	1.567	1.6	2.05
2.2	0.45	2.2	1.908	1.648	1.713	1.75	2.25
2.5	0.45	2.5	2.208	1.948	2.013	2.06	2.6
3	0.5	3	2.675	2.387	2.459	2.5	3.1
3.5	0.6	3.5	3.11	2.764	2.85	2.9	3.6
4	0.7	4	3.545	3.141	3.242	3.3	4.1
4.5	0.75	4.5	4.013	3.58	3.688	3.7	4.6
5	0.8	5	4.48	4.019	4.134	4.2	5.1
6	1	6	5.35	4.773	4.917	5	6.1
7	1	7	6.35	5.773	5.917	6	7.2
8	1.25	8	7.188	6.466	6.647	6.8	8.2
9	1.25	9	8.188	7.466	7.647	7.8	9.2
10	1.5	10	9.026	8.16	8.376	8.5	10.2
11	1.5	11	10.026	9.16	9.376	9.5	11.2
12	1.75	12	10.863	9.853	10.106	10.2	12.2
14	2	14	12.701	11.546	11.835	12	14.25
16	2	16	14.701	13.546	13.835	14	16.25
18	2.5	18	16.376	14.933	15.294	15.5	18.25
20	2.5	20	18.376	16.933	17.294	17.5	20.25
22	2.5	22	20.376	18.933	19.294	19.5	22.25
24	3	24	22.051	20.319	20.752	21	24.25
27	3	27	25.051	23.319	23.752	24	27.25
30	3.5	30	27.727	25.706	26.211	26.5	30.5
33	3.5	33	30.727	28.706	29.211	29.5	33.5
36	4	36	33.402	31.093	31.67	32	36.5
39	4	39	36.402	34.093	34.67	35	39.5
42	4.5	42	39.077	36.479	37.129	37.5	42.5
45	4.5	45	42.077	39.479	40.129	40.5	45.5
48	5	49	44.752	41.866	42.587	43	48.5
52	5	52	48.752	45.866	46.587	47	53
56	5.5	56	52.428	49.252	50.046	50.5	57