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Resistor Color Code Calculator

Decode 4, 5, and 6-band resistors, understand tolerances, and learn how the EIA colour code works.

Visualize your resistor

Use the colour pickers below to match the bands on your component and read the calculated value instantly.

Band configuration:
Band 1Band 2Band 3MultiplierTolerance

Select band colours

Band 1

First significant digit

Black

Band 2

Second significant digit

Black

Band 3

Third significant digit

Black

Multiplier

Multiplier (10ⁿ factor)

Black

Tolerance

Tolerance (%)

Brown · ±1%

How the colour code is calculated

  1. Identify the tolerance band first; it is usually spaced further from the lead.
  2. Read bands toward the other end. The first two (or three) bands are the significant digits.
  3. Convert the multiplier band into a power of ten (e.g. red = 10², gold = 10⁻¹) and multiply the digits.
  4. Apply the tolerance percentage to find the minimum and maximum possible values.
  5. If present, use the temperature coefficient to estimate drift: ΔR = R · tempco · ΔT.

Source: IEC 60062 / EIA RS-279 — Colour coding for fixed resistors. Values shown assume base-10 series.

Reference table

ColourDigitMultiplierToleranceTempco (ppm/°C)
Black
010⁰250
Brown
110¹±1%100
Red
210²±2%50
Orange
310³15
Yellow
410⁴25
Green
510⁵±0.5%
Blue
610⁶±0.25%10
Violet
710⁷±0.1%5
Grey
810⁸±0.05%
White
910⁹1
Gold
10⁻¹±5%
Silver
10⁻²±10%
No band
±20%