Resistor Color Code Calculator

Decode 4, 5, and 6-band resistor color codes to find the resistance, tolerance, and min/max value.

Resistor Color Code Calculator tool

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Example

Input: 4-band resistor: yellow, violet, red, gold

Result: 4.7 kΩ ±5% (4,700 Ω; range 4.465 kΩ to 4.935 kΩ)

Yellow (4) and violet (7) give 47, red multiplies by 100 for 4,700 ohms, and gold means a 5% tolerance (4,700 x 0.05 = 235 ohms).

Resistor Color Code Chart

ColorDigitMultiplierTolerance
Black0x1-
Brown1x101%
Red2x1002%
Orange3x1,000-
Yellow4x10,000-
Green5x100,0000.5%
Blue6x1,000,0000.25%
Violet7x10,000,0000.1%
Grey8x100,000,0000.05%
White9x1,000,000,000-
Gold-x0.15%
Silver-x0.0110%
  1. Choose the resistor type - 4-band, 5-band, or 6-band - matching the physical resistor you are reading.
  2. Select the color of each band in order from left to right using the dropdown menus.
  3. View the decoded resistance value, tolerance percentage, and min/max resistance range.
  4. For 6-band resistors, also select the temperature coefficient band to see its value in ppm/K.
  5. Use the visual resistor diagram to verify your color band selections match the physical component.

How to Read Resistor Color Bands

Resistor color bands give a resistor's value in ohms. On a 4-band resistor, the first two bands are digits, the third is a multiplier and the fourth is the tolerance. Yellow, violet, red, gold means 4 and 7, times 100, so 4,700 ohms (4.7 kilohms) within 5%.

Start reading from the end where the bands are grouped together. The tolerance band, often gold or silver, usually sits a little apart at the other end. Gold and silver never appear as the first band. Precision 5-band resistors use three digit bands before the multiplier, so brown, black, black, red, brown is 100 x 100 = 10,000 ohms at 1%. A 6-band resistor adds a last band for the temperature coefficient. That is how much the value drifts as the part heats up, in parts per million per kelvin (ppm/K).

Choose 4, 5 or 6 bands and pick each color from the menus. The tool draws the resistor so you can hold it up to the real part. It then shows the value in ohms, kilohms or megohms, the exact value and the tolerance. It also gives the lowest and highest real value the part may have. A 4.7 kilohm resistor at 5% can be anywhere from 4,465 to 4,935 ohms. Colors can be hard to tell apart under poor light, especially red, orange and brown. If in doubt, check with a multimeter. Once you know the value, the Ohm's Law Calculator shows the current and power at your voltage.

Formula / How It Works

Resistance = (Band1 x 10 + Band2) x Multiplier (4-band) | Resistance = (Band1 x 100 + Band2 x 10 + Band3) x Multiplier (5-band)

Frequently Asked Questions

Each color stands for a number: black 0, brown 1, red 2, orange 3, yellow 4, green 5, blue 6, violet 7, grey 8 and white 9. The digit bands spell out the number. The multiplier band gives the power of ten to multiply by. The last band shows the tolerance, such as gold for 5% or brown for 1%.
Read from the end where the first band sits closest to the lead. The tolerance band is usually gold or silver, and it often has a wider gap before it. If the result is not a standard value, such as 4.7 k, 10 k or 220 ohms, try reading from the other end.
Brown (1) and black (0) make 10. Red means multiply by 100, which gives 1,000 ohms, or 1 kilohm. Gold means a 5% tolerance, so the real value falls between 950 and 1,050 ohms. It is one of the most common resistors in hobby kits.
In the multiplier spot, gold means times 0.1 and silver means times 0.01. They are used for low values under 10 ohms. For example, red, red, gold, gold is 22 x 0.1 = 2.2 ohms at 5%. In the tolerance spot, gold means 5% and silver 10%.
A 5-band resistor has three digit bands instead of two, so it can show values more precisely. They are mostly used for 1% or tighter tolerance parts. A 4-band part usually has a 5% or 10% tolerance. The multiplier and tolerance bands work the same way in both.

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