Most color codes read from left to right with a gap on the right side and round components may have the gap on the bottom. The EIA standard color code used in electronics is simple although through the year’s colors and the color bars have remained basically the same, some of their values have changed with technology. These are some of the color codes I use when working on electronics. Looking up the components values and properties from its color code is easier than reverse engineering from scratch. I can reverse engineer the circuit and guess at what the appropriate replacement component is and its value or I can look up the color code and select a modern replacement that will work. Older devices often have color coded components not seen in newer electronics today, and the exact component quite often is no longer available. I work on many older electronic devices capacitors and resistors can go out of tolerance with time. They are still in use on many devices used in electronics today. The color codes we all know and love come from EIA standards, (Electronics Industries Association) and they were used on almost every device at one time or another, even vacuum tubes. When I looked up color codes here at Instructables, I was surprised to find just a few one page Instructables on component color codes. Let us know how we can improve.I have been reverse engineering since before the advent of solid state circuits. Visit the Terms of Use and Privacy Policy for this site. Visit the Tables page to view reference tables such as Maximum Ampacity for Current-Carrying Conductors. To calculate wire ampacity for a circuit, use the Wire Ampacity Calculator or the Advanced Wire Ampacity Calculator.įor long conductor runs where voltage drop may be an issue, use the Voltage Drop Calculator to determine proper conductor sizing and maximumĬircuit length. To calculate wire size for a circuit, use the Wire Size Calculator or the Advanced Wire Size Calculator. Produces a resistance value of 123 * 100 = 12.3 kΩ with a ± 5% tolerance. Band 4: Multiplier (determines order of magnitude)įor example, a resistor with a color band pattern of brown, red, orange, red, gold yields the first digit as 1, the second digit as 2, the third digit as 3, and a multiplier of 10,000.Band 3: Third significant figure (additional digit of precision).Band 1: First significant figure (left-most digit).Resistance values can be calculated from a 5-band resistor color code as follows: Note: Tolerance values in % of full resistance range.

4 band resistor color code chart