resistors in electronics

The resistance and tolerance of a resistor are usually indicated by a series of four or five colored rings or dots. Three or four of the bands are equally spaced; the last one is by itself.

If the solitary ring is placed on the right, the other bands have the following meaning, reading from the left:

Band 4 bands
(20%, 10% or 5%)
5 bands
(1% or 2%)
1 first digit
of resistance value
first digit
of resistance value
2 second digit
of resistance value
second digit
of resistance value
3 multiplier third digit
of resistance value
4 tolerance multiplier
5 tolerance

For more information, see:

High precision resistors may have their value printed on them.

A black body indicates an uninsulated composition resistor. Colored bodies are insulated.

If the color band for the first digit is twice the width of the other bands, the resistor is wire-wound.

If there is no such band, the tolerance is ±20%. Tolerance is sometimes indicated by a letter.

home | materials index | search |  contact drawing of envelope |  contributors | 
help | privacy | terms of use