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Resistor colour code

Read a four- or five-band resistor to find its resistance and tolerance.

Nominal resistance and tolerance from the selected colour bands. Verify the component marking and power rating.

Band colours

1st

First significant digit band (IEC 60062).

2nd

Second significant digit band.

Mult

The multiplier scales the value formed by the digit bands.

Tol

The tolerance is the permitted percentage deviation from the nominal resistance.

Results

Select band colours, then Calculate to decode resistance.

How this works

4-band: digit, digit, multiplier, tolerance. 5-band: three digits, multiplier, tolerance.

Related calculators

Check the stated method and limits against your installation. Results are calculation aids, not certification.

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Calculation model 2026-11-02.1