Free workshop tool
Resistor Colour Code Calculator
Decode a standard 4-band resistor from its colour bands and see the resistance value and tolerance instantly.
4-band resistors. This tool uses two significant digits, one multiplier band and one tolerance band. For 5-band precision resistors, use the manufacturer’s marking reference or a dedicated 5-band chart.
Colour reference
Standard resistor digits
Digit colours
Black 0, brown 1, red 2, orange 3, yellow 4, green 5, blue 6, violet 7, grey 8 and white 9.
Reading direction
The tolerance band is usually separated slightly from the other bands. Gold and silver are commonly tolerance bands, which helps identify the reading direction.
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