Conversion Tools calculator
Resistor Color Code Calculator
Decode 4-band, 5-band, and 6-band resistor color codes into resistance, tolerance, and temperature coefficient. For example, red-violet-yellow-brown-brown on a 5-band resistor gives 2.74 kΩ with ±1% tolerance, or a range from 2.7126 kΩ to 2.7674 kΩ.
Updated July 10, 2026
Example Calculations
How to Use
How to Decode Resistor Color Bands
Select the band count first. Use 4 bands for two significant digits, 5 bands for three significant digits, and 6 bands when the resistor also has a temperature coefficient band.
1. Read the Significant Digits
| Band Count | Digit Bands | Multiplier Band | Other Bands |
|---|---|---|---|
| 4-band | Bands 1 and 2 | Band 3 | Band 4 is tolerance |
| 5-band | Bands 1, 2, and 3 | Band 4 | Band 5 is tolerance |
| 6-band | Bands 1, 2, and 3 | Band 4 | Band 5 is tolerance; band 6 is ppm/°C |
2. Apply Multiplier and Tolerance
For a 5-band resistor marked red, violet, yellow, brown, brown: red = 2, violet = 7, yellow = 4, brown multiplier = x10, and brown tolerance = ±1%. The result is 274 x 10 = 2,740 Ω, or 2.74 kΩ at ±1%.
3. Confirm Ambiguous Parts
Gold and silver are usually tolerance or multiplier bands, so they often help identify the reading direction. If the colors are faded, the spacing is unclear, or the resistor is still installed in a circuit, confirm the value with a meter before using it in repair or design work.
Common Applications
More applications. Open to review 2 additional use cases.
Frequently Asked Questions
How do I read a 4-band resistor?
The first two bands are significant digits, the third band is the multiplier, and the fourth band is tolerance. For example, brown-black-red-gold is 10 x 100 = 1,000 Ω with ±5% tolerance.
How do I read a 5-band resistor?
The first three bands are significant digits, the fourth band is the multiplier, and the fifth band is tolerance. Red-violet-yellow-brown-brown gives 274 x 10 = 2.74 kΩ with ±1% tolerance.
What does the 6th resistor band mean?
On a 6-band resistor, the sixth band is the temperature coefficient in ppm/°C. It estimates how much the resistance changes with temperature and is most useful for precision or temperature-sensitive circuits.
Why do some resistor bands look reversed?
Tolerance bands such as gold, silver, brown, red, green, blue, violet, or gray are commonly placed at the end, sometimes with a wider gap. If the part is symmetrical or faded, verify the value with a multimeter or datasheet.
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