The E series of preferred numbers was chosen such that when a component is manufactured it will end up in a range of roughly equally spaced values with geometric progression on a logarithmic scale. Each E series subdivides each decade magnitude into steps of 3, 6, 12, 24, 48, 96, 192 values.

Subdivisions of E3 to E192 ensure the maximum error will be divided in the order of 40%, 20%, 10%, 5%, 2%, 1%, 0.5%. Also, the E192 series is used for 0.25% and 0.1% tolerance resistors.

E6 series

1.01.52.23.34.76.8

E12 series

1.01.21.51.82.22.7
3.33.94.75.66.88.2

E24 series

1.01.11.21.31.51.6
1.82.02.22.42.73.0
3.33.63.94.34.75.1
5.66.26.87.58.29.1

E48 series

1.001.051.101.151.211.27
1.331.401.471.541.621.69
1.781.871.962.052.152.26
2.372.492.612.742.873.01
3.163.323.483.653.834.02
4.224.424.644.875.115.36
5.625.906.196.496.817.15
7.507.878.258.669.099.53

E96 series

1.001.021.051.071.101.13
1.151.181.211.241.271.30
1.331.371.401.431.471.50
1.541.581.621.651.691.74
1.781.821.871.911.962.00
2.052.102.152.212.262.32
2.372.432.492.552.612.67
2.742.802.872.943.013.09
3.163.243.323.403.483.57
3.653.743.833.924.024.12
4.224.324.424.534.644.75
4.874.995.115.235.365.49
5.625.765.906.046.196.34
6.496.656.816.987.157.32
7.507.687.878.068.258.45
8.668.879.099.319.539.76

E192 series

1.001.011.021.041.051.06
1.071.091.101.111.131.14
1.151.171.181.201.211.23
1.241.261.271.291.301.32
1.331.351.371.381.401.42
1.431.451.471.491.501.52
1.541.561.581.601.621.64
1.651.671.691.721.741.76
1.781.801.821.841.871.89
1.911.931.961.982.002.03
2.052.082.102.132.152.18
2.212.232.262.292.322.34
2.372.402.432.462.492.52
2.552.582.612.642.672.71
2.742.772.802.842.872.91
2.942.983.013.053.093.12
3.163.203.243.283.323.36
3.403.443.483.523.573.61
3.653.703.743.793.833.88
3.923.974.024.074.124.17
4.224.274.324.374.424.48
4.534.594.644.704.754.81
4.874.934.995.055.115.17
5.235.305.365.425.495.56
5.625.695.765.835.905.97
6.046.126.196.266.346.42
6.496.576.656.736.816.90
6.987.067.157.237.327.41
7.507.597.687.777.877.96
8.068.168.258.358.458.56
8.668.768.878.989.099.20
9.319.429.539.659.769.88

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