Resistor Color Code Calculator: 3, 4, 5 and 6 Bands

Resistor Color Code Calculator

Select the band count and resistor colors to decode nominal resistance, tolerance and, for six bands, temperature coefficient.

Read from the end opposite the wider-spaced tolerance band. Select colors in the order they appear.

Resistor color code formula

The first two bands are significant digits on 3- and 4-band resistors; the first three are significant digits on 5- and 6-band resistors. The next band is the multiplier.

Resistance (Ω) = significant digits × multiplier

Gold multiplies by 0.1 and silver by 0.01. Three-band resistors have no tolerance band; this calculator uses the standard ±20% convention. Four bands add tolerance, five bands use three digits plus multiplier and tolerance, and six bands add a temperature coefficient.

Examples checked independently

  • 4 bands: red–violet–yellow–gold = 27 × 10,000 Ω = 270 kΩ ±5%; range 256.5–283.5 kΩ.
  • 5 bands: brown–black–black–red–brown = 100 × 100 Ω = 10 kΩ ±1%; range 9.9–10.1 kΩ.
  • 6 bands: same first five bands plus red = 10 kΩ ±1%, 50 ppm/°C.
  • 3 bands: yellow–violet–red = 47 × 100 Ω = 4.7 kΩ ±20%; range 3.76–5.64 kΩ.

Limits and reading tips

This calculator decodes common 3-, 4-, 5- and 6-band markings. It does not identify a component by image, verify its measured resistance, or determine power suitability. Leading black digits and zero-ohm jumper markings are outside this decoder; verify those parts with a multimeter. Color appearance varies with lighting, age and manufacturer. If the order is unclear or the component is safety-critical, verify with a multimeter and manufacturer documentation. The displayed temperature-coefficient values are the common values used here; check the component specification for its applicable standard.

There are no input units to convert. The value is calculated in ohms and displayed as Ω, kΩ, MΩ or GΩ. Tolerance is a nominal manufacturing range, not a guarantee of in-circuit behavior.

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