How to Read Resistor Color Bands

Resistor color codes are used to indicate the value of a resistor. The first two or three bands represent significant digits, the next band is the multiplier, and the last band is the tolerance. The band closest to the edge of the resistor is usually band 1. In most cases, the tolerance band (often gold or silver) is at the opposite end of the resistor, helping you determine the correct direction for reading.

Table of Resistor Values by Color

Color	Significant Figures	Multiplier	Tolerance
Black	0	x1	-
Brown	1	x10	±1%
Red	2	x100	±2%
Orange	3	x1,000	-
Yellow	4	x10,000	-
Green	5	x100,000	±0.5%
Blue	6	x1,000,000	±0.25%
Violet	7	x10,000,000	±0.1%
Gray	8	-	±0.05%
White	9	-	-
Gold	-	x0.1	±5%
Silver	-	x0.01	±10%

How to Calculate Resistor Value

To calculate the resistance, identify the bands and their colors. The first two or three bands represent the significant digits. Multiply the value by the multiplier band. Lastly, the tolerance band gives the possible variation in resistance value. For example:

Red (2), Violet (7), Orange (x1,000), Gold (±5%)

This would represent a 27,000Ω resistor with a ±5% tolerance.

Using the Resistor in Circuits

When resistors are connected in series, the total resistance is the sum of the individual resistances. In parallel, the total resistance can be calculated using the formula:

1 / R_total = 1 / R1 + 1 / R2 + ... + 1 / Rn