What does the color code on a resistor indicate?

• A. The resistance value
• B. The date the resistor was manufactured
• C. The hours of operation
• D. The discharge time

Answer: (A)

Colors on a resistor encode its resistance value. In the common four-band scheme, the first two bands give the digits of the value, the third band is the multiplier (how many zeros to add), and the fourth band shows the tolerance (how close the actual value is to the stated value). Colors map to digits as black 0, brown 1, red 2, orange 3, yellow 4, green 5, blue 6, violet 7, gray 8, white 9. The multiplier uses the same color scale to indicate powers of ten, and the tolerance band (often gold for 5% or silver for 10%) tells how precise the value is. Some resistors use a five-band scheme with three digits, a multiplier, and a tolerance. The color code does not indicate manufacturing date, hours of operation, or discharge time.