Reading Resistor Color Codes

Resistor Colors with Associated Values:

Black	Brown	Red	Orange	Yellow	Green	Blue	Violet	Gray	White
0	1	2	3	4	5	6	7	8	9

How to read the code

Find the tolerance band, it will typically be gold ( +/-5% Tolerance) and sometimes silver (+/-10%).

Starting from the other end, identify the first band - write down the number associated with that color; in the example below, Brown is 1.

Now 'read' the next color, here it is Black so write down a '0' next to the one. (you should have '10' so far.)

Now read the third or 'multiplier' band and write down that number of zeros.

In this example, the Red band implies two zeros (10²). If the 'multiplier' band is Black (for zero) don't write any zeros down.

If the 'multiplier' band is Gold move the decimal point one to the left. If the 'multiplier' band is Silver move the decimal point two places to the left.

Example: 1 K-Ohm Resistor (1000 Ohms): Brown Band indicates a most significant digit of One Black Band indicates a digit of Zero Red Band indicates a Multiplier of 10^2 (thus 10 x 10^2 = 1000) Gold Band indicates a +/-5% tolerance (i.e. 950 to 1050 Ohms) Ignore the 5^th band for now

Note: If the resistor has one more band past the tolerance band it is a quality band. We do not have this band in our lab.

Read the number as the '% Failure rate per 1000 hour'. This rating is determined with full wattage being applied to the resistors. (To get better failure rates, resistors are typically specified to have twice the needed wattage dissipation that the circuit produces) 1% resistors have three bands to read digits to the left of the multiplier. They have a different temperature coefficient in order to provide the 1% tolerance.