Preferred Resistor Values

Resistors are available in a number of standard ranges, often called 'preferred values' These ranges, or series, are set out by the Electronic Industries Association (EIA), and are E3, E6, E12, E24, E48, E96 and E192. The number after the 'E' denotes the number of values the series contains per decade. The E3 and E6 series aren't really used these days; the most common series is probably E24. The series are logarithmic and are derived from the resistor tolerance; resistors with a tighter tolerance can have more values in the series that won't overlap one another. The series are sometimes referred to by the tolerance, the two being related as follows:

E3: 50% tolerance
E6: 20% tolerance
E12: 10% tolerance
E24: 5% tolerance
E48: 2% tolerance
E96: 1% tolerance
E192: less than 1% tolerance

When designing a circuit you need to round calculated resistor values to a preferred value. Normally this would be the value closest to the calculated one for the series you are using. However in some circumstances its better to round up to the next higher value, such as with current limiting resistors where using a value smaller than calculated could overload a component. The tables below show the values for some of the more common preferred series.

E12 Series:

E24 Series:

E48 Series:

The values of the decade 100-1000 for the E48 series are:

100, 105, 110, 115, 121, 127, 133, 140, 147, 154, 162, 169, 178, 187, 196, 205, 215, 226, 237, 249, 261, 274, 287, 301, 316, 332, 348, 365, 383, 402, 422, 442, 464, 487, 511, 536, 562, 590, 619, 649, 681, 715, 750, 787, 825, 866, 909, 953

Multiply or divide the values by 10 for other decades.

E96 Series:

The values of the decade 100-1000 for the E96 series are:

100, 102, 105, 107, 110, 113, 115, 118, 121, 124, 127, 130, 133, 137, 140, 143, 147, 150, 154, 158, 162, 165, 169, 174, 178, 182, 187, 191, 196, 200, 205, 210, 215, 221, 226, 232, 237, 243, 249, 255, 261, 267, 274, 280, 287, 294, 301, 309, 316, 324, 332, 340, 348, 357, 365, 374, 383, 392, 402, 412, 422, 432, 442, 453, 464, 475, 487, 499, 511, 523, 536, 549, 562, 576, 590, 604, 619, 634, 649, 665, 681, 698, 715, 732, 750, 768, 787, 806, 825, 845, 866, 887, 909, 931, 953, 976,

Multiply or divide the values by 10 for other decades.

E192 Series:

The values of the decade 100-1000 for the E192 series are:

100, 101, 102, 104, 105, 106, 107, 109, 110, 111, 113, 114, 115, 117, 118, 120, 121, 123, 124, 126, 127, 129, 130, 132, 133, 135, 137, 138, 140, 142, 143, 145, 147, 149, 150, 152, 154, 156, 158, 160, 162, 164, 165, 167, 169, 172, 174, 176, 178, 180, 182, 184, 187, 189, 191, 193, 196, 198, 200, 203, 205, 208, 210, 213, 215, 218, 221, 223, 226, 229, 232, 234, 237, 240, 243, 246, 249, 252, 255, 258, 261, 264, 267, 271, 274, 277, 280, 284, 287, 291, 294, 298, 301, 305, 309, 312, 316, 320, 324, 328, 332, 336, 340, 344, 348, 352, 357, 361, 365, 370, 374, 379, 383, 388, 392, 397, 402, 407, 412, 417, 422, 427, 432, 437, 442, 448, 453, 459, 464, 470, 475, 481, 487, 493, 499, 505, 511, 517, 523, 530, 536, 542, 549, 556, 562, 569, 576, 583, 590, 597, 604, 612, 619, 626, 634, 642, 649, 657, 665, 673, 681, 690, 698, 706, 715, 723, 732, 741, 750, 759, 768, 777, 787, 796, 806, 816, 825, 835, 845, 856, 866, 876, 887, 898, 909, 920, 931, 942, 953, 965, 976, 988

Multiply or divide the values by 10 for other decades.

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