Toolman

Resistor colour codes

The bands on a resistor are two digits, a multiplier and a tolerance. This gives the code for every value that is actually manufactured at ±5% — the E24 series — and each value has its own page answering the question from either end: the bands you need for a value, or the value a set of bands means.

The tables the code is built from

ColourDigitMultiplierTolerance
black0× 1
brown1× 10± 1%
red2× 100± 2%
orange3× 1,000
yellow4× 10,000
green5× 100,000± 0.5%
blue6× 1,000,000± 0.25%
violet7± 0.1%
grey8
white9
gold÷ 10± 5%
silver÷ 100± 10%

Which end to read from

The tolerance band sits slightly further from the other three, and it is gold or silver on most resistors. Neither gold nor silver is a digit colour, so a gold or silver band is telling you which end is the last one — start reading from the other. On a resistor with no gold or silver at all, the wider gap before the last band is the only clue, and it is worth measuring rather than guessing.

Why these values and not round ones

E24 is 24 values per decade, spaced so that the ±5% ranges of neighbouring values very nearly meet. There is no gap left between one value and the next, so there is nothing to be gained by making anything in between — which is why a shop sells 4.7 kΩ and 5.1 kΩ but not 5 kΩ. The ±10% series, E12, uses half as many values for the same reason.

1 Ω to 9.1 Ω

ValueBands
1 Ωbrown black gold gold
1.1 Ωbrown brown gold gold
1.2 Ωbrown red gold gold
1.3 Ωbrown orange gold gold
1.5 Ωbrown green gold gold
1.6 Ωbrown blue gold gold
1.8 Ωbrown grey gold gold
2 Ωred black gold gold
2.2 Ωred red gold gold
2.4 Ωred yellow gold gold
2.7 Ωred violet gold gold
3 Ωorange black gold gold
3.3 Ωorange orange gold gold
3.6 Ωorange blue gold gold
3.9 Ωorange white gold gold
4.3 Ωyellow orange gold gold
4.7 Ωyellow violet gold gold
5.1 Ωgreen brown gold gold
5.6 Ωgreen blue gold gold
6.2 Ωblue red gold gold
6.8 Ωblue grey gold gold
7.5 Ωviolet green gold gold
8.2 Ωgrey red gold gold
9.1 Ωwhite brown gold gold

10 Ω to 91 Ω

ValueBands
10 Ωbrown black black gold
11 Ωbrown brown black gold
12 Ωbrown red black gold
13 Ωbrown orange black gold
15 Ωbrown green black gold
16 Ωbrown blue black gold
18 Ωbrown grey black gold
20 Ωred black black gold
22 Ωred red black gold
24 Ωred yellow black gold
27 Ωred violet black gold
30 Ωorange black black gold
33 Ωorange orange black gold
36 Ωorange blue black gold
39 Ωorange white black gold
43 Ωyellow orange black gold
47 Ωyellow violet black gold
51 Ωgreen brown black gold
56 Ωgreen blue black gold
62 Ωblue red black gold
68 Ωblue grey black gold
75 Ωviolet green black gold
82 Ωgrey red black gold
91 Ωwhite brown black gold

100 Ω to 910 Ω

ValueBands
100 Ωbrown black brown gold
110 Ωbrown brown brown gold
120 Ωbrown red brown gold
130 Ωbrown orange brown gold
150 Ωbrown green brown gold
160 Ωbrown blue brown gold
180 Ωbrown grey brown gold
200 Ωred black brown gold
220 Ωred red brown gold
240 Ωred yellow brown gold
270 Ωred violet brown gold
300 Ωorange black brown gold
330 Ωorange orange brown gold
360 Ωorange blue brown gold
390 Ωorange white brown gold
430 Ωyellow orange brown gold
470 Ωyellow violet brown gold
510 Ωgreen brown brown gold
560 Ωgreen blue brown gold
620 Ωblue red brown gold
680 Ωblue grey brown gold
750 Ωviolet green brown gold
820 Ωgrey red brown gold
910 Ωwhite brown brown gold

1 kΩ to 9.1 kΩ

ValueBands
1 kΩbrown black red gold
1.1 kΩbrown brown red gold
1.2 kΩbrown red red gold
1.3 kΩbrown orange red gold
1.5 kΩbrown green red gold
1.6 kΩbrown blue red gold
1.8 kΩbrown grey red gold
2 kΩred black red gold
2.2 kΩred red red gold
2.4 kΩred yellow red gold
2.7 kΩred violet red gold
3 kΩorange black red gold
3.3 kΩorange orange red gold
3.6 kΩorange blue red gold
3.9 kΩorange white red gold
4.3 kΩyellow orange red gold
4.7 kΩyellow violet red gold
5.1 kΩgreen brown red gold
5.6 kΩgreen blue red gold
6.2 kΩblue red red gold
6.8 kΩblue grey red gold
7.5 kΩviolet green red gold
8.2 kΩgrey red red gold
9.1 kΩwhite brown red gold

10 kΩ to 91 kΩ

ValueBands
10 kΩbrown black orange gold
11 kΩbrown brown orange gold
12 kΩbrown red orange gold
13 kΩbrown orange orange gold
15 kΩbrown green orange gold
16 kΩbrown blue orange gold
18 kΩbrown grey orange gold
20 kΩred black orange gold
22 kΩred red orange gold
24 kΩred yellow orange gold
27 kΩred violet orange gold
30 kΩorange black orange gold
33 kΩorange orange orange gold
36 kΩorange blue orange gold
39 kΩorange white orange gold
43 kΩyellow orange orange gold
47 kΩyellow violet orange gold
51 kΩgreen brown orange gold
56 kΩgreen blue orange gold
62 kΩblue red orange gold
68 kΩblue grey orange gold
75 kΩviolet green orange gold
82 kΩgrey red orange gold
91 kΩwhite brown orange gold

100 kΩ to 910 kΩ

ValueBands
100 kΩbrown black yellow gold
110 kΩbrown brown yellow gold
120 kΩbrown red yellow gold
130 kΩbrown orange yellow gold
150 kΩbrown green yellow gold
160 kΩbrown blue yellow gold
180 kΩbrown grey yellow gold
200 kΩred black yellow gold
220 kΩred red yellow gold
240 kΩred yellow yellow gold
270 kΩred violet yellow gold
300 kΩorange black yellow gold
330 kΩorange orange yellow gold
360 kΩorange blue yellow gold
390 kΩorange white yellow gold
430 kΩyellow orange yellow gold
470 kΩyellow violet yellow gold
510 kΩgreen brown yellow gold
560 kΩgreen blue yellow gold
620 kΩblue red yellow gold
680 kΩblue grey yellow gold
750 kΩviolet green yellow gold
820 kΩgrey red yellow gold
910 kΩwhite brown yellow gold

1 MΩ to 9.1 MΩ

ValueBands
1 MΩbrown black green gold
1.1 MΩbrown brown green gold
1.2 MΩbrown red green gold
1.3 MΩbrown orange green gold
1.5 MΩbrown green green gold
1.6 MΩbrown blue green gold
1.8 MΩbrown grey green gold
2 MΩred black green gold
2.2 MΩred red green gold
2.4 MΩred yellow green gold
2.7 MΩred violet green gold
3 MΩorange black green gold
3.3 MΩorange orange green gold
3.6 MΩorange blue green gold
3.9 MΩorange white green gold
4.3 MΩyellow orange green gold
4.7 MΩyellow violet green gold
5.1 MΩgreen brown green gold
5.6 MΩgreen blue green gold
6.2 MΩblue red green gold
6.8 MΩblue grey green gold
7.5 MΩviolet green green gold
8.2 MΩgrey red green gold
9.1 MΩwhite brown green gold

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