BravoCalc

Resistor Color Code Calculator

Understanding Resistor Color Codes

Resistors are electronic components that limit the flow of electric current in a circuit. Most resistors use a color-coding system to indicate their resistance value and tolerance. This calculator helps you decode these color bands to determine the exact resistance value.

How to Read Resistor Color Bands

Resistors typically have 4, 5, or 6 color bands. The first bands represent significant digits, followed by a multiplier band, and finally a tolerance band. Some precision resistors also include a temperature coefficient band.

4-Band Resistors

  • 1st band: First significant digit
  • 2nd band: Second significant digit
  • 3rd band: Multiplier
  • 4th band: Tolerance

5-Band Resistors

  • 1st band: First significant digit
  • 2nd band: Second significant digit
  • 3rd band: Third significant digit
  • 4th band: Multiplier
  • 5th band: Tolerance

6-Band Resistors

  • 1st band: First significant digit
  • 2nd band: Second significant digit
  • 3rd band: Third significant digit
  • 4th band: Multiplier
  • 5th band: Tolerance
  • 6th band: Temperature coefficient (ppm/°C)

Color Code Values

ColorDigit ValueMultiplierToleranceTemp. Coefficient
Black0×100 (1)-250 ppm/°C
Brown1×101 (10)±1%100 ppm/°C
Red2×102 (100)±2%50 ppm/°C
Orange3×103 (1K)±3%15 ppm/°C
Yellow4×104 (10K)±4%25 ppm/°C
Green5×105 (100K)±0.5%20 ppm/°C
Blue6×106 (1M)±0.25%10 ppm/°C
Violet7×107 (10M)±0.1%5 ppm/°C
Gray8×108 (100M)±0.05%1 ppm/°C
White9×109 (1G)--
Gold-×10-1 (0.1)±5%-
Silver-×10-2 (0.01)±10%-
None--±20%-

Common Resistor Values

Resistors are manufactured in standard values according to the E-series. The most common are:

  • E12 series (±10% tolerance): 10, 12, 15, 18, 22, 27, 33, 39, 47, 56, 68, 82
  • E24 series (±5% tolerance): E12 plus 11, 13, 16, 20, 24, 30, 36, 43, 51, 62, 75, 91

These values are then multiplied by powers of 10 to create the full range of available resistors.