Resistor Color Code Calculator

Decode color bands to resistance values, or find the bands for any resistance. Supports 4, 5, and 6 band resistors.

Select bands above
Select band colors above to calculate resistance.

How to Use the Resistor Color Code Calculator

  1. Bands→Value — choose 4, 5, or 6 band mode, then select a color for each band from the dropdowns. The resistance value and tolerance update instantly.
  2. Value→Bands — enter a resistance value and select the unit (Ω, kΩ, MΩ). The tool shows the nearest standard E-series value and its color bands.
  3. Reference — a quick reference card for all band colors and their digit, multiplier, tolerance, and TC values.

Understanding Resistor Color Codes

Resistor color codes are a standardized marking system for electronic components. Because resistors are small cylindrical components and numeric labels would be difficult to read from many angles, the IEC 60062 standard defines a system of colored bands painted around the resistor body. Each color corresponds to a digit (0-9), a multiplier power of ten, a tolerance percentage, or a temperature coefficient. Reading the bands from left to right (with the tolerance band on the right, or the gap toward the right) gives the resistance value.

The color sequence is: Black=0, Brown=1, Red=2, Orange=3, Yellow=4, Green=5, Blue=6, Violet=7, Grey=8, White=9. This order is universal. The tolerance band uses additional colors: Gold=±5%, Silver=±10%, Brown=±1%, Red=±2%, Green=±0.5%, Blue=±0.25%, Violet=±0.1%.

4-Band vs 5-Band vs 6-Band

The most common resistors use 4 bands: two digit bands, one multiplier, and one tolerance band. For example, Brown (1) - Black (0) - Red (×100) - Gold (±5%) = 1000Ω = 1kΩ ±5%. Precision resistors use 5 bands: three digit bands, one multiplier, and one tolerance. This allows representing values like 1.05kΩ that require a third significant digit. 6-band resistors add a temperature coefficient (TC) band, important for precision analog circuits where temperature drift must be known.

Reading Direction

The tolerance band (Gold or Silver) is always on the right. For 5-band resistors, the first band is closest to one end. If you can't tell which end to start from, check: Gold and Silver never appear as digit bands, so if you see one of those at the left end, flip the resistor. Some resistors have a larger gap between the multiplier and tolerance bands to indicate the read direction.

Mnemonic for Remembering Colors

The classic mnemonic for the digit order (0=Black, 1=Brown, 2=Red, 3=Orange, 4=Yellow, 5=Green, 6=Blue, 7=Violet, 8=Grey, 9=White) is "Bad Boys Race Our Young Girls But Violet Generally Wins." Many variations exist; use whichever resonates with you. After a few hours of reading real resistors, the colors become second nature and the mnemonic becomes unnecessary.

Standard Resistor Series (E-Series)

Resistors are manufactured in standardized value series: E12 (12 values per decade), E24 (24 values, ±5% tolerance), E48, E96 (±1%), and E192 (±0.5%). These series are logarithmically spaced so that the possible value range is covered with minimum gaps. If you need an exact resistance not available in a series, use a combination of resistors in series or parallel to achieve the target value.

Frequently Asked Questions

A 4-band resistor has two digit bands, one multiplier, and one tolerance band. Read first two as digits (e.g., Brown=1, Black=0 → 10), multiply by the multiplier (e.g., Red=100 → 10×100=1000), last band is tolerance (Gold=±5%). So Brown-Black-Red-Gold = 1kΩ ±5%.
A 5-band resistor has three digit bands for more precision, plus a multiplier and tolerance band. 5-band resistors are used for precision components where 4-band accuracy (2 significant figures) is insufficient.
The 6th band is the temperature coefficient (TC), measured in ppm/°C. It indicates how much the resistance changes per degree Celsius. Brown = 100 ppm/°C, Red = 50 ppm/°C.
Gold has two meanings: as a multiplier it means ×0.1 (divide by 10), and as a tolerance band it means ±5%. Gold is never used as a digit band.
The classic mnemonic is "Bad Boys Race Our Young Girls But Violet Generally Wins" for Black(0) Brown(1) Red(2) Orange(3) Yellow(4) Green(5) Blue(6) Violet(7) Grey(8) White(9).