Dimension of ANSI/ASME B18.2.2 Hex Nuts

The ANSI/ASME B18.2.2 standard refers to the specification for Hex Nuts. It defines the dimensions, tolerances, and thread sizes of these nuts to ensure compatibility and proper functioning when paired with corresponding bolts or screws.

Nominal Size	Basic Major Thread Diameter	Width Across Flats, F		Width Across Corners, G		Thickness Hex Nuts, H
		Min.	Max.	Min.	Max.	Min.	Max.
1/4	0.25	0.428	0.438	0.488	0.505	0.212	0.226
5/16	0.3125	0.489	0.500	0.557	0.577	0.258	0.273
3/8	0.375	0.551	0.563	0.628	0.650	0.320	0.337
7/16	0.4375	0.675	0.688	0.768	0.794	0.365	0.385
1/2	0.50	0.736	0.750	0.840	0.866	0.427	0.448
9/16	0.5625	0.861	0.875	0.982	1.010	0.473	0.496
5/8	0.625	0.922	0.938	1.051	1.083	0.535	0.559
3/4	0.75	1.088	1.125	1.240	1.299	0.617	0.665
7/8	0.875	1.269	1.312	1.447	1.516	0.724	0.776
1	1.00	1.450	1.500	1.653	1.732	0.831	0.887
1 1/8	1.125	0.631	1.688	1.859	1.949	0.939	0.999
1 1/4	1.25	1.812	1.875	2.066	2.165	1.030	1.094
1 3/8	1.375	2.994	2.062	2.273	2.382	1.138	1.206
1 1/2	1.50	2.175	2.250	2.480	2.598	1.245	1.317
1 5/8	1.625	2.350	2.430	2.679	2.805	1.364	1.416
1 3/4	1.75	2.538	2.625	2.893	3.031	1.460	1.540
1 7/8	1.875	2.722	2.813	3.103	3.247	1.567	1.651
2	2.00	2.900	3.000	3.306	3.464	1.675	1.763
2 1/4	2.25	3.263	3.375	3.719	3.897	1.890	1.986
2 1/2	2.50	3.625	3.750	4.133	4.330	2.105	2.209
2 3/4	2.75	3.988	4.125	2.622	2.742	1.433	1.505
3	3.00	4.350	4.500	4.959	5.196	2.534	2.654
3 1/4	3.25	4.713	4.875	5.373	5.629	2.749	2.877
3 1/2	3.50	5.075	5.250	5.786	6.062	2.964	3.100
3 3/4	3.75	5.438	5.625	6.199	6.495	3.178	3.322
4	4.50	5.800	6.000	6.612	6.928	3.393	3.545

Referring to the official ANSI/ASME B18.2.2 standard documentation.