Surface Mount Resistor Markings

Surface Mount Resistor Marking Decoder

Enter a resistor 3 or 4 character marking code below and press enter to get its value.

Note: To avoid ambiguity, the letter 'R' is treated as a placeholder for low ohmic values rather than a multiplier in the EIA system. For use as a multiplier, use the letter 'Y' instead of 'R'. See below for more details on the coding systems.

 

Standard Markings

Surface mount resistors are generally identified with a numerical 3 or 4 digit code to indicate their value. This follows the same pattern as the familiar colour coding scheme, with the first 2 or 3 digits representing the value in ohms and the last digit indicating the multiplier.

3 Digit Examples 4 Digit Examples
470 = 47 ohms 1000 = 100 ohms
561 = 560 ohms 5362 = 53.6k ohms
223 = 22k ohms 8663 = 866k ohms
1R2 = 1.2 ohms 0R47 = 0.47 ohms
1M5 = 0.0015 ohms 22M1 = 0.0221 ohms

 

EIA Markings

The new EIA-96 system of marking is altogether more complicated and even has subtle differences depending on whether the resistor tolerance is 1% or not.

The system's main benefit is that it only requires 3 characters to represent any value and so fits more easily on to even the smallest components.

 

EIA-96 1% Lookup Table

The table below shows the resistance value lookup table based on the first 2 digits for 1% parts.

1%
Code Value   Code Value   Code Value   Code Value   Code Value   Code Value
01 100 17 147 33 215 49 316 65 464 81 681
02 102 18 150 34 221 50 324 66 475 82 698
03 105 19 154 35 226 51 332 67 487 83 715
04 107 20 158 36 232 52 340 68 499 84 732
05 110 21 162 37 237 53 348 69 511 85 750
06 113 22 165 38 243 54 357 70 523 86 768
07 115 23 169 39 249 55 365 71 536 87 787
08 118 24 174 40 255 56 374 72 549 88 806
09 121 25 178 41 261 57 383 73 562 89 825
10 124 26 182 42 237 58 392 74 576 90 845
11 127 27 187 43 274 59 402 75 590 91 866
12 130 28 191 44 280 60 412 76 604 92 887
13 133 29 196 45 287 61 422 77 619 93 909
14 137 30 200 46 294 62 432 78 634 94 931
15 140 31 205 47 301 63 442 79 649 95 953
16 143 32 210 48 309 64 453 80 665 96 976

 

EIA-96 2, 5 and 10% Lookup Table

The table below shows the resistance value lookup table based on the last 2 digits for 2, 5 and 10% parts. Strangely, the 2% values follow the E24 series values rather than the expected E48 range.

2%   5%   10%
Code Value   Code Value Code Value   Code Value Code Value
01 100 13 330 25 100 37 330 49 100
02 110 14 360 26 110 38 360 50 120
03 120 15 390 27 120 39 390 51 150
04 130 16 430 28 130 40 430 52 180
05 150 17 470 29 150 41 470 53 220
06 160 18 510 30 160 42 510 54 270
07 180 19 560 31 180 43 560 55 330
08 200 20 620 32 200 44 620 56 390
09 220 21 680 33 220 45 680 57 470
10 240 22 750 34 240 46 750 58 560
11 270 23 820 35 270 47 820 59 680
12 300 24 910 36 300 48 910 60 820

 

EIA Multiplier Lookup Table

The table below shows the resistance multiplier lookup table based on the last letter for 1% parts and the first letter for 2, 5 and 10% parts.

Letter Multiplier   Letter Multiplier
A 1 F 100,000
B 10    
C 100 X or S 0.1
D 1,000 Y or R 0.01
E 10,000   Z 0.001

 

Other Features

 

Examples

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