Reading Axial Resistor Values

Determining a resistor's value from its band markings.

Axial Resistor Colored Bands

Axial resistors, the kind that is most often used when prototyping, have color coded bands that specify the resistance value and tolerance of the resistor. They usually come in 4 or 5 band flavors, with 5 band resistors being more precise.

To read a banded resistor, align it so that the three (or four) closely spaced bands are on the left, and the furthest spaced band is on the right. Then, use the following chart to determine the values from left to right:

4-band resistor color chart

The first 2 (or 3 bands, on a 5-band resistor) specify the resistance value, and the 3rd (or 4th) specify the magnitude multiplier.

Sample Reading

For example, the resistor shown above has the following values:

  • Brown = 1
  • Blue = 6
  • Black = 0
  • Orange = 1k Magnitude Multiplier
  • Gold = 5% Tolerance

Therefore, the resistor has 160Ω * 1k = 160kΩ, with a tolerance of ±5%.

Next - Resistor Tolerance


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