Screw Thread Conversion Table

MAJOR DIAMETER (Converted to INCH Decimals)

NOMINAL DIAMETER (mm) MAJOR DIAMETER
mm INCH
M 1 1 .0393
M 1.1 1.1 .0433
M 1.2 1.2 .0472
M 1.4 1.4 .0551
M 1.6 1.6 .0629
M 1.8 1.8 .0708
M 2 2 .0787
M 2.2 2.2 .0866
M 2.3 2.3 .0905
M 2.5 2.5 .0984
M 2.6 2.6 .1023
M 3 3 .1181
M 3.5 3.5 .1378
M 4 4 .1574
M 4.5 4.5 .1771
M 5 5 .1968
M 6 6 .2362
M 7 7 .2755
M 8 8 .3149
M 10 10 .3937
M 12 12 .4724
M 14 14 .5511
M 16 16 .6299
M 18 18 .7086
M 20 20 .7874
M 22 22 .8661
M 24 24 .9448
M 27 27 1.0629
M 30 30 1.181
M 33 33 1.299
M 36 36 1.417
M 39 39 1.535
M 42 42 1.654
M 45 45 1.772
M 48 48 1.890
M 52 52 2.047
M 56 56 2.205
M 60 60 2.362
M 64 64 2.520
M 68 68 2.677
M 72 72 2.835
M 76 76 2.992
M 80 80 3.150
M 85 85 3.346
M 90 90 3.543
M 95 95 3.740
M 100 100 3.937
M 105 105 4.134
M 110 110 4.331
M 115 115 4.538
M 120 120 4.724
M 125 125 4.921
M 130 130 5.118
M 135 135 5.315
M 140 140 5.512
M 145 145 5.709
M 150 150 5.906

THREAD PITCH (Converted to Number of Threads per Inch)

PITCH (mm) Approx. Threads per Inch
0.08 317.5
0.09 282.25
0.1 254
0.125 203.25
0.15 169.25
0.175 145.25
0.2 127
0.225 113
0.25 101.5
0.3 84.75
0.35 72.5
0.4 63.5
0.45 56.5
0.5 50.75
0.6 42.25
0.7 36.25
0.75 33.75
0.8 31.75
0.9 25.25
1 25.5
1.25 20.25
1.5 17
1.75 14.25
2 12.75
2.5 10.25
3 8.5
3.5 7.25
4 6.25
5 5
5.5 4.5
6 4.25

*All information is strictly informative