Resistor Color Code Calculator
Select the first digit, second digit, multiplier, and tolerance bands to estimate nominal resistor value and tolerance range.
- Nominal resistance
- ohm
- Nominal resistance
- kohm
- Nominal resistance
- Mohm
- Tolerance
- %
- Minimum resistance
- ohm
- Maximum resistance
- ohm
Calculation details
- Calculation basis
- Boundary
Recent results
Formulas
- Two digit value = first digit x 10 + second digit
- Nominal resistance = two digit value x multiplier
- Minimum resistance = nominal resistance x (1 - tolerance percent / 100)
- Maximum resistance = nominal resistance x (1 + tolerance percent / 100)
Use this calculator
Convert four resistor color bands into nominal resistance and tolerance range.
Read the result
Review the calculated values with their displayed units and assumptions. The result is a planning aid for the stated inputs, not a final equipment or installation decision.
Check before final work
This is an educational resistor color estimate. Verify physical band order, manufacturer markings, tolerance, wattage, temperature coefficient, and circuit requirements before using a component.
FAQs
Which end of the resistor should I start from?
Start from the end with the grouped bands. The tolerance band is usually spaced farther from the digit and multiplier bands.
Does this include 5-band resistors?
No. This first version decodes common four-band resistors only. Use manufacturer data for precision parts.