Electrical and electronics
Resistor colour code calculator (4, 5 and 6 band)
Read a 4-, 5- or 6-band resistor colour code, or find the bands for a value, with tolerance, temperature coefficient and the nearest E-series value.
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Result
Method and limits
IEC 60062 codes resistance with coloured bands read from the end where the bands are bunched. Four-band parts carry two significant digits, five- and six-band parts three; then comes a multiplier band, a tolerance band and, on six-band parts, a temperature-coefficient band.
| Colour | Digit | Multiplier | Tolerance | Temp. coefficient |
|---|---|---|---|---|
| Black | 0 | ×1 | — | 250 ppm/K |
| Brown | 1 | ×10 | ±1% | 100 ppm/K |
| Red | 2 | ×100 | ±2% | 50 ppm/K |
| Orange | 3 | ×1 k | — | 15 ppm/K |
| Yellow | 4 | ×10 k | — | 25 ppm/K |
| Green | 5 | ×100 k | ±0.5% | 20 ppm/K |
| Blue | 6 | ×1 M | ±0.25% | 10 ppm/K |
| Violet | 7 | ×10 M | ±0.1% | 5 ppm/K |
| Grey | 8 | ×100 M | ±0.05% | 1 ppm/K |
| White | 9 | ×1 G | — | — |
| Gold | — | ×0.1 | ±5% | — |
| Silver | — | ×0.01 | ±10% | — |
| Pink | — | ×0.001 | — | — |
| None | — | — | ±20% | — |
Worked example: yellow (4), violet (7), red (×100), gold (±5%) = 47 × 100 = 4.7 kΩ ± 5%, so 4.465 kΩ to 4.935 kΩ.
Preferred values. IEC 60063 E-series space values evenly on a logarithmic scale: En has n values per decade, close to 10^(i/n). E6, E12 and E24 use the historical rounded values (2.7, 3.3, 4.7 …); E48, E96 and E192 are 10^(i/192) rounded to three figures, except 9.20 in E192. The nearest value is chosen on a logarithmic scale, as the series are spaced.
Limits
Colours fade and brown, red and orange are easy to confuse under warm light: measure with a meter if in doubt. Surface-mount parts use printed number codes instead of colours.
References
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