Understanding your calculation
Method, example and limitations
How the calculation works
Resistor color bands encode significant digits, a multiplier and tolerance. The number of bands determines how to read those values.
Example to check
A four-band brown-black-red-gold resistor represents 10 × 100 = 1,000 Ω with a ±5% tolerance.
Before using the result
Read the bands from the correct end. A nominal resistance is not a measurement; power rating, temperature coefficient and component condition also matter.