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EIA Standard Resistor & Capacitor Values



Standard Values

These are normalised to 100R. For different values just move the decimal point left or right.

E3 (±50%) E6 (±20%) E12 (±10%) E24 (±5%) E48 (±2%) E96 (±1%) E192
(±0.5%, ±0.25%, ±0.1%)
100 100 100 100 100 100 100
101
102 102
104
105 105 105
106
107 107
109
110 110 110 110
111
113 113
114
115 115 115
117
118 118
120
120 120 121 121 121
123
124 124
126
127 127 127
129
130 130
132
130 133 133 133
135
137 137
138
140 140 140
142
143 143
145
150 150 150 147 147 147
149
150 150
152
154 154 154
156
158 158
160
160 162 162 162
164
165 165
167
169 169 169
172
174 174
176
180 180 178 178 178
180
182 182
184
187 187 187
189
191 191
193
200 196 196 196
198
200 200
203
205 205 205
208
210 210
213
220 220 220 220 215 215 215
218
221 221
223
226 226 226
229
232 232
234
240 237 237 237
240
243 243
246
249 249 249
252
255 255
258
270 270 261 261 261
264
267 267
271
274 274 274
277
280 280
284
300 287 287 287
291
294 294
298
301 301 301
305
309 309
312
330 330 330 316 316 316
320
324 324
328
332 332 332
336
340 340
344
360 348 348 348
352
357 357
361
365 365 365
370
374 374
379
390 390 383 383 383
388
392 392
397
402 402 402
407
412 412
417
430 422 422 422
427
432 432
437
442 442 442
448
453 453
459
470 470 470 470 464 464 464
470
475 475
481
487 487 487
493
499 499
505
510 511 511 511
517
523 523
530
536 536 536
542
549 549
556
560 560 562 562 562
569
576 576
583
590 590 590
597
604 604
612
620 619 619 619
626
634 634
642
649 649 649
657
665 665
673
680 680 680 681 681 681
690
698 698
706
715 715 715
723
732 732
741
750 750 750 750
759
768 768
777
787 787 787
796
806 806
816
820 820 825 825 825
835
845 845
856
866 866 866
876
887 887
898
910 909 909 909
920
931 931
942
953 953 953
965
976 976
988

Note: there is a slight mismatch between the E6-E24 series and the E48-E192 series in the above table (for example 120Ω in the E24 series does not align with 120Ω in the E192 series). One day I might get round to fixing it.


Ratio Table


The following table give ratios between each value in the E24 resistor series to two decimal places. The values not in E12 are italicised.

To use the table simply read off the row and column to find the ratio between them. For example, to find the ratio between 2.2 and 1.8, scan the top row to find "2.2", then down the column until you meet the "1.8" row, giving 1.22.

 1.001.101.201.301.501.601.802.002.202.402.703.003.303.603.904.304.705.105.606.206.807.508.209.10
1.001.001.101.201.301.501.601.802.002.202.402.703.003.303.603.904.304.705.105.606.206.807.508.209.10
1.100.911.001.091.181.361.451.641.822.002.182.452.733.003.273.553.914.274.645.095.646.186.827.458.27
1.200.830.921.001.081.251.331.501.671.832.002.252.502.753.003.253.583.924.254.675.175.676.256.837.58
1.300.770.850.921.001.151.231.381.541.691.852.082.312.542.773.003.313.623.924.314.775.235.776.317.00
1.500.670.730.800.871.001.071.201.331.471.601.802.002.202.402.602.873.133.403.734.134.535.005.476.07
1.600.630.690.750.810.941.001.131.251.381.501.691.882.062.252.442.692.943.193.503.884.254.695.125.69
1.800.560.610.670.720.830.891.001.111.221.331.501.671.832.002.172.392.612.833.113.443.784.174.565.06
2.000.500.550.600.650.750.800.901.001.101.201.351.501.651.801.952.152.352.552.803.103.403.754.104.55
2.200.450.500.550.590.680.730.820.911.001.091.231.361.501.641.771.952.142.322.552.823.093.413.734.14
2.400.420.460.500.540.630.670.750.830.921.001.131.251.381.501.631.791.962.132.332.582.833.133.423.79
2.700.370.410.440.480.560.590.670.740.810.891.001.111.221.331.441.591.741.892.072.302.522.783.043.37
3.000.330.370.400.430.500.530.600.670.730.800.901.001.101.201.301.431.571.701.872.072.272.502.733.03
3.300.300.330.360.390.450.480.550.610.670.730.820.911.001.091.181.301.421.551.701.882.062.272.482.76
3.600.280.310.330.360.420.440.500.560.610.670.750.830.921.001.081.191.311.421.561.721.892.082.282.53
3.900.260.280.310.330.380.410.460.510.560.620.690.770.850.921.001.101.211.311.441.591.741.922.102.33
4.300.230.260.280.300.350.370.420.470.510.560.630.700.770.840.911.001.091.191.301.441.581.741.912.12
4.700.210.230.260.280.320.340.380.430.470.510.570.640.700.770.830.911.001.091.191.321.451.601.741.94
5.100.200.220.240.250.290.310.350.390.430.470.530.590.650.710.760.840.921.001.101.221.331.471.611.78
5.600.180.200.210.230.270.290.320.360.390.430.480.540.590.640.700.770.840.911.001.111.211.341.461.63
6.200.160.180.190.210.240.260.290.320.350.390.440.480.530.580.630.690.760.820.901.001.101.211.321.47
6.800.150.160.180.190.220.240.260.290.320.350.400.440.490.530.570.630.690.750.820.911.001.101.211.34
7.500.130.150.160.170.200.210.240.270.290.320.360.400.440.480.520.570.630.680.750.830.911.001.091.21
8.200.120.130.150.160.180.200.220.240.270.290.330.370.400.440.480.520.570.620.680.760.830.911.001.11
9.100.110.120.130.140.160.180.200.220.240.260.300.330.360.400.430.470.520.560.620.680.750.820.901.00

This table can be used in a number of ways. For example:

  • A typical post-fade amp is a non-inverting amplifier with a gain of +10dB. In absolute terms the amplifier needs a gain of 3.16. For the non-inverting amplifier configuration we need a resistor ratio of 2.16. From the table above it looks like 3.9 and 1.8 are the closest, with a ratio of 2.17. In a circuit you could then use a 3k9 and 1k8 resistors.

Common Ratios


Some ratios are rather useful, and I have listed then here. They are based on a minimal set of values giving many useful ratios: 10, 11, 15, 22, 33, 51, 75.

Resistors (A:B) Ratio (1:n) Reciprocal Potential Divider - ABTM:BTOP Potential Divider - BBTM:ATOP Uses
10:10 1 1 1/2 1/2 6dB attenuator, x2 (+6dB) gain for non-inverting OA
10:15 1.5 2/3 2/5 3/5
22:33 1.5 2/3 2/5 3/5
11:22 2 1/2 1/3 2/3 10dB attenuator, x2 (+6dB) gain for inverting OA
10:22 2.2 5/16 11/16 +10dB gain for non-inverting OA
15:33 2.2 5/16 11/16 +10dB gain for non-inverting OA
11:33 3 1/3 1/4 3/4
10:33 3.3 +10dB gain for inverting OA
15:75 5 1/5 1/6 5/6


Power Table


The table below shows the minimum permissible resistor values for a range of common resistor power ratings and some common voltages. Note that this table does not allow for any derating.

 0.063W (63mW)0.1W (100mW)0.25W (250mW)0.4W (400mW)0.6W (600mW)1W
3V3172.9108.943.627.218.110.9
5V396.8250.0100.062.541.725.0
9V1285.7810.0324.0202.5135.081.0
12V2285.71440.0576.0360.0240.0144.0
15V3571.42250.0900.0562.5375.0225.0
18V5142.93240.01296.0810.0540.0324.0
24V9142.95760.02304.01440.0960.0576.0
30V14285.79000.03600.02250.01500.0900.0

For example, consider an LED across a 15V supply. Allow 2 volts for the LED, and we want 10mA. We have 13 volts to drop, so we need a 1300 Ohm resistor. Using the above table look at the 12V row (closest voltage) and then scan along to the column with 576.0 Ohms. Read off the resistor power rating at the top of the column: 250mW in this case. To compare, the actual power dissipated would be 130mW - so we could not use a 100mW resistor, the next common size up being 250mW.


Colour Codes


ColourUnitMultiplierTolerance (± %)Temp. Coeff (ppm/°C)
Black 01  
Brown 1101 (F)100
Red 21002 (G)50
Orange 31,0003 (H)15
Yellow 410,000 25
Green 5100,0000.5 (D) 
Blue 61,000,0000.25 (Q)10
Violet 710,000,0000.1 (B)5
Grey 8100,000,0000.05 (A) 
White 91,000,000,000 1
Gold  0.15 (J) 
Silver  0.0110 (K) 
Pink   20 (M) 

The letters in the tolerance column apply to smaller components and capacitors. E.g. a SIL resistor marked "473K" is 47k, ±10%.


Reading Resistor Color Codes


TypeBand
123456
4 BandValueValueMultiplierTolerance  
5 BandValueValueValueMultiplierTolerance 
6 BandValueValueValueMultiplierToleranceTemp Coeff.

Note: If the tolerance band is missing (for 4- or 5-band), assume ±20%.

Temperature Compensation Resistors

Temperature compensation resistors ("tempcos" or TCRs) use a similar marking scheme, where:

TypeBand
12345
5 BandValueValueMultiplerTempCoTempCo

The last two bands indicate the temperature coefficient:

ValueCoefficient (ppm/°C)
303000
333300
353500
393900

Note that this temperature coefficient is different from the standard marking scheme above: firstly, the values are much larger (thousands of ppm compared to tens), and the marking scheme uses two bands, not one.

Examples:

  • --(            )--680k, ±5%
  • --(               )--53k6, ±2%
  • --(                  )--1k37, ±1%, 50ppm/°C

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