Resistor Color Code Calculator
Read 4, 5, and 6-band resistor colors, resistance, tolerance range, and temperature coefficient.
R = significant digits × color multiplierCalculations stay in your browser. Share links contain the input values you choose to share.
How to use this calculator
- Choose 4, 5, or 6 bands to match the resistor.
- Select each color in reading order from left to right.
- Check the resistor illustration and read resistance and tolerance limits.
- For six bands, read the final band’s temperature coefficient in ppm/K.
A quick worked example
Yellow, violet, red, gold gives 47 × 100 Ω = 4.7 kΩ ±5%. Its nominal tolerance limits are 4.465 kΩ and 4.935 kΩ. Brown, black, black, red, brown gives 10 kΩ ±1%.
A few useful answers
What changes between 4, 5, and 6 bands?
Four bands encode two significant digits, a multiplier, and tolerance. Five bands encode three digits, a multiplier, and tolerance. Six bands add a temperature coefficient after the tolerance band.
Which end do I start from?
Start with the significant digit bands. The tolerance band often has a larger gap before it; gold or silver at one end is a useful clue. If the orientation is uncertain, check the actual part documentation or measure it.
What does the sixth band mean?
It indicates the temperature coefficient of resistance, in ppm/K. A coefficient magnitude of 100 ppm/K corresponds to 0.01% per kelvin. Supported common mappings are brown 100, red 50, orange 15, yellow 25, blue 10, and violet 5.
Does this tell me the power rating?
The color bands modeled here indicate nominal resistance, tolerance, and optionally TCR. Power rating, maximum voltage, and construction depend on the actual component and its datasheet.
Model & assumptions: Common 4/5/6-band resistance codes using the Vishay reference. Manufacturer-specific extra bands, reliability markings, zero-ohm links, and other schemes are outside this decoder. TCR options follow the cited chart and may depend on model.
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