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The electronic color code discussed here is used to indicate the values or ratings of electronic components, very commonly for resistors, but also for capacitors.  The electronic color code was developed in the early 1920s by the Radio Manufacturer’s Association, (now part of Electronic Industries Alliance), and was published as EIA-RS-279. The current international standard is IEC 60062.

Colorbands were commonly used (especially on resistors) because they were easily printed on tiny components, decreasing construction costs.  However, there were drawbacks, especially for color blind people.  Overheating of a component, or dirt accumulation, may make it impossible to distinguish brown from red from orange.  Advances in printing technology have made printed numbers practical for small components, which are often found in modern electronics.

Resistor values are always coded in ohms, capacitors in picofarads (pF). The standard color code per EN 60062:2005 is as follows:

  • band A is first significant figure of component value
  • band B is the second significant figure
  • band C is the decimal multiplier
  • band D if present, indicates tolerance of value in percent (no color means 20%)

For example, a resistor with bands of yellow, violet, red, and gold will have first digit 4 (yellow in table below), second digit 7 (violet), followed by 2 (red) zeros: 4,700 ohms.  Gold signifies that the tolerance is ±5%, so the real resistance could lie anywhere between 4,465 and 4,935 ohms.  All coded components will have at least two value bands and a multiplier; other bands are optional.

If you have interest in receiving a copy of this Free Cheat Sheet guide, just send an email to MyFeedback@dee-inc.com containing “Resistor/Capacitor Guide” in the subject line, and include your contact information.

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