Method
Nominal resistance = (10×first digit + second digit) × 10^multiplier; tolerance gives lower and upper bounds.
Everyday worksheet
Resistor Color Code Calculator
Decode a four-band resistor from digit, multiplier and tolerance colors and show nominal range and preferred notation.
The calculation runs locally. Results include the intermediate values, unit conversions and assumptions needed to audit the answer.
Method, assumptions and practical use
How the Resistor Color Code Calculator works
Nominal resistance = (10×first digit + second digit) × 10^multiplier; tolerance gives lower and upper bounds. Inputs stay in this browser, and the result table exposes conversions and assumptions for independent checking.
Interpret the result
The color bands encode a nominal manufactured value and allowed percentage range, not a measured resistance.
Check the assumptions
This simplified page covers four-band numeric decoding; temperature coefficient and six-band markings need additional inputs.
Local calculation
Everything runs in this browser. Inputs are not sent to an external calculator.
Rounding
Displayed values may be rounded for readability while calculations use full floating-point precision unless the tool explicitly uses exact integers.
Scope
This simplified page covers four-band numeric decoding; temperature coefficient and six-band markings need additional inputs.
Simple by design
Three steps to a clearer number.
Enter your details
Use realistic values in each field. You can change them anytime.
Calculate instantly
The formula runs locally, so there is no account or waiting time.
Use the result
Treat the answer as a practical estimate for your next decision.