What is Resistor Color Code Calculator?
Resistor Color Code Calculator helps you read a four-band resistor's resistance and tolerance from its colours.
The main result is four-band resistance, with a breakdown of tolerance, minimum resistance and maximum resistance. The formula, example and assumptions below explain how to interpret it.
How to use Resistor Color Code Calculator
Use the example to get familiar with the form, then enter your own figures. Any rates in the example are illustrative. Check the field labels and units before calculating.
- Gather first digit band, second digit band, multiplier band and tolerance band. Use values from the same situation or reporting period.
- Replace the example first digit band with your own value, then complete the other fields. Check the displayed units and each selected option.
- Select Calculate and read four-band resistance with its result breakdown. Change one input and calculate again to compare a second scenario. Reset restores the original example.
- Choose first digit band from Brown, Red, Orange, Yellow, Green, Blue, Violet, Grey and White.
- Choose second digit band from Black, Brown, Red, Orange, Yellow, Green, Blue, Violet, Grey and White.
- Choose multiplier band from Black, Brown, Red, Orange, Yellow, Green, Blue, Violet, Grey, White, Gold and Silver.
- Choose tolerance band from Brown ±1%, Red ±2%, Gold ±5% and Silver ±10%.
Resistor Color Code Calculator: a worked example
With the inputs below, the result is 1,000 Ω (four-band resistance). Follow the example, then replace these illustrative values with your own.
| Input or output | Example value |
|---|---|
| First digit band | Brown |
| Second digit band | Black |
| Multiplier band | Red |
| Tolerance band | Gold ±5% |
| Four-band resistance | 1,000 Ω |
| Tolerance | 5 % |
| Minimum resistance | 950 Ω |
| Maximum resistance | 1,050 Ω |
Understanding the Resistor Color Code result
Read four-band resistance alongside tolerance, minimum resistance and maximum resistance. These describe different parts of the same calculation.
Displayed results use a readable number of decimal places. When checking a result by hand, keep extra precision until the last step. To compare scenarios, change one input at a time and keep the others fixed.
- Example Tolerance: 5 %
- Example Minimum resistance: 950 Ω
- Example Maximum resistance: 1,050 Ω
Resistor Color Code Calculator: assumptions and common mistakes
A useful estimate starts with the right inputs. Check the following assumptions and limits before applying the result to your situation.
- DC, single-phase and three-phase calculations use different relationships. Equipment selection also depends on installation conditions and applicable standards.
For wider guidance, visit Bureau of Indian Standards. The formula and scope of this specific tool are stated on this page.
