Resistor Color Code Calculator

Each band on a resistor stands for a digit, a multiplier, a tolerance or a temperature coefficient, and this reads them in either direction. Pick the colors you see and it returns the resistance in ohms, the engineering value and the range the part is allowed to fall in. The value tab does the reverse, giving the bands to look for and saying whether your number can be written exactly with two or three digits. The tables are the published IEC ones, including the sixth band in parts per million per kelvin. Read a real resistor from the end where the bands are crowded together, with the tolerance band last.

Calculator Type

Two digit bands, a multiplier and a tolerance. Set the tolerance to "No band" for a three band resistor, which is the 20% class.

Band 1 (first digit)

Band 2 (second digit)

Band 3 (multiplier)

Band 4 (tolerance)

Widget

Three digit bands, a multiplier and a tolerance. This is the usual precision resistor.

Band 1 (first digit)

Band 2 (second digit)

Band 3 (third digit)

Band 4 (multiplier)

Band 5 (tolerance)

Widget

A five band resistor with a sixth band for the temperature coefficient in parts per million per kelvin.

Band 1 (first digit)

Band 2 (second digit)

Band 3 (third digit)

Band 4 (multiplier)

Band 5 (tolerance)

Band 6 (temperature coefficient)

Widget