Free electronics calculators
Type in your numbers, get the answer, and see why it works. Every calculator comes with a simple explanation and a worked example.
- LED Resistor CalculatorWhich resistor stops your LED from burning out?
- Resistor Colour Code CalculatorRead a resistor's value from its coloured bands.
- Voltage Divider CalculatorTurn a big voltage into a smaller one with two resistors.
- Ohm's Law CalculatorAny two of volts, amps, ohms or watts give you the rest.
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