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Resistor Color Code Calculator

Pick the colors you see on a resistor — 4, 5 or 6 bands — to get its resistance, tolerance range and temperature coefficient. Or go the other way: type a value such as 4.7k, 470R or 2M2 and get the bands to look for, with a warning if the value has to be rounded and which standard E-series it belongs to.

Quick examples

Usually set apart from the others, often gold or silver on 4-band parts.

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Result4.7 kΩ ±5%
Resistance
4,700 Ω
Allowed range
4.465 kΩ to 4.935 kΩ
Minimum
4,465 Ω
Maximum
4,935 Ω
Bands, left to right
Yellow, Violet, Red, Gold
Standard series
E6, E12, E24
Note
—

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      Formula

      4 bands: resistance = (digit 1, digit 2) × multiplier, then tolerance
      5 bands: resistance = (digit 1, digit 2, digit 3) × multiplier, then tolerance
      6 bands: as 5 bands, plus a temperature coefficient band in ppm/K
      Digits: black 0, brown 1, red 2, orange 3, yellow 4, green 5, blue 6, violet 7, grey 8, white 9
      Multiplier: 10 to the power of the color’s digit; gold × 0.1, silver × 0.01
      Range = resistance × (1 ± tolerance ÷ 100)

      How to use it

      1. Hold the resistor with the tolerance band — usually gold or silver, or set slightly apart — on the right.
      2. Choose how many bands it has and pick each color from left to right.
      3. Read the value and the range it is guaranteed to fall within.
      4. To find colors for a value, choose a “find bands” option and type the resistance.

      Worked examples

      Yellow, violet, red, gold: 4 and 7, times 100, ±5%

      Result
      4.7 kΩ ±5%
      Resistance
      4,700 Ω
      Minimum
      4,465 Ω
      Maximum
      4,935 Ω
      Allowed range
      4.465 kΩ to 4.935 kΩ
      Standard series
      E6, E12, E24

      Brown, black, black, red, brown (5 bands): 100 × 100 = 10 kΩ ±1%

      Result
      10 kΩ ±1%
      Resistance
      10,000 Ω
      Minimum
      9,900 Ω
      Maximum
      10,100 Ω
      Standard series
      E6, E12, E24, E48, E96

      Orange, orange, black, brown, brown, red (6 bands): 330 × 10 = 3.3 kΩ ±1%, 50 ppm/K

      Result
      3.3 kΩ ±1%, 50 ppm/K
      Resistance
      3,300 Ω

      Brown, black, gold, gold: 10 × 0.1 = 1 Ω

      Result
      1 Ω ±5%
      Resistance
      1 Ω
      Maximum
      1.05 Ω

      Color bands for a 220 Ω, 5% resistor

      Result
      Red, Red, Brown, Gold
      Resistance
      220 Ω
      Bands, left to right
      220 Ω ±5%

      Color bands for 4.7 kΩ at 1% on a 5-band resistor

      Result
      Yellow, Violet, Black, Brown, Brown
      Resistance
      4,700 Ω

      0.47 Ω needs a silver multiplier

      Result
      Yellow, Violet, Silver, Gold
      Resistance
      0.47 Ω

      1,234 Ω cannot be shown with two digits, so 4 bands round it to 1.2 kΩ

      Result
      Brown, Red, Red, Gold
      Resistance
      1,200 Ω
      Note
      Rounded to 1.2 kΩ, the nearest value 4 bands can show
      Standard series
      E12, E24

      Reading the bands the right way round

      Gold and silver never appear as the first band, so if one end is gold or silver, start from the other end. On 5 and 6-band parts the tolerance band is usually brown (±1%) and can be confused with a brown first digit; look for the wider gap, which sits before the tolerance band.

      If the colors are hard to tell apart — red against orange, brown against red under warm light — measure with a multimeter. A reading inside the allowed range confirms the code.

      Tolerance and temperature colors

      Tolerance: brown ±1%, red ±2%, green ±0.5%, blue ±0.25%, violet ±0.1%, gold ±5%, silver ±10%, and no band ±20%.

      The sixth band gives the temperature coefficient: how much the resistance drifts per degree. Brown is 100 ppm/K, red 50, yellow 25, orange 15, blue 10 and violet 5. A 10 kΩ, 100 ppm/K resistor changes by about 1 Ω for each °C.

      Why some values do not exist

      Resistors are made in preferred-number series. The E12 series — 10, 12, 15, 18, 22, 27, 33, 39, 47, 56, 68, 82 and their multiples of ten — covers most hobby kits, E24 adds a value between each, and precision 1% parts follow E96. If the series row says a value is not standard, pick the nearest one that is.

      Questions people ask

      What is yellow, violet, red, gold?

      4.7 kΩ ±5%: yellow 4, violet 7, red × 100 = 4,700 Ω, anywhere from 4,465 to 4,935 Ω.

      What are the colors for a 10k resistor?

      Brown, black, orange, gold on a 4-band part (1, 0, × 1,000, ±5%). On a 5-band 1% part: brown, black, black, red, brown.

      What are the colors for a 220 ohm resistor?

      Red, red, brown on a 4-band part, followed by gold for ±5%. On a 5-band part: red, red, black, black, then the tolerance band.

      What does a gold multiplier band mean?

      Multiply by 0.1. Brown, black, gold is 10 × 0.1 = 1 Ω; yellow, violet, silver is 47 × 0.01 = 0.47 Ω.

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