Common Resistor

Resistors are color coded for easy reading.

To determine the value of a given resistor look for the gold or silver tolerance band and rotate the resistor as in the photo above. (Tolerance band to the right). Look at the 1st color band and determine its color. This maybe difficult on small or oddly colored resistors. Now look at the chart and match the "1st & 2nd color band" color to the "Digit it represents". Write this number down.

Now look at the 2nd color band and match that color to the same chart. Write this number next to the 1st Digit.

The Last color band is the number you will multiply the result by. Match the 3rd color band with the chart under multiplier. This is the number you will multiple the other 2 numbers by. Write it next to the other 2 numbers with a multiplication sign before it. Example : 2 2 x 1,000.

To pull it all together now, simply multiply the first 2 numbers (1st number in the tens column and 2nd in the ones column) by the Multiplier

Example:

  • First color is red which is 2
  • Second color is black which is 0
  • third color is yellow which is 10,000
  • Tolerance is silver which is 10%

    It all adds up to:

    2 0 x 10,000 = 200,000 Ohms

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    1st. & 2nd Color Band

    Digit it Represents

    Multiplier

      BLACK

    BROWN

    RED

    ORANGE

    YELLOW

    GREEN

    BLUE

    VIOLET

    GRAY

    WHITE

    0

    1

    2

    3

    4

    5

    6

    7

    8

    9

    X 1

    X 10

    X 100

    X 1,000 or 1K

    X 10,000 or 10K

    X 100,000 or 100k

    X 1,000,000 or 1M

    Silver is divide by 100

    Gold is divide by 10

    Tolerances

    Gold = 5%

    Silver = 10%

    None = 20%

    Resistors are never the exact value that the color codes indicate. Therefore manufacturers place a tolerance color band on the resistor to tell you just how accurate this resistor is made. It is simply a measurement of the imperfections. Gold means the resistor is within 5% of being dead-on accurate. Silver being within 10% and no color band being within 20%. To determine the exact range that the resistor may be, take the value of the resistor and multiply it by 5,10, 0r 20%. That is the number that the resistor may go either way.

    Example: A 1,000 Ohm resistor with a gold band maybe any value between 950 to 1050 Ohms.

    Example: A 22,000 Ohm resistor with a silver band maybe any value between 19,800 and 24,200 Ohms.