Free Electronics Tools Stay updated with the Latest in electronics tools, Arduino projects, ESP8266, and DIY circuits. Engineering Tools Capacitor Color CodeCalculate capacitance using color code Ohm's Law CalculatorCalculate current and voltage Inductance CalculatorCalculate inductance LED Resistor CalculatorCalculate LED resistance Op-Amp Gain CalculatorCalculate amplifier gain SMD Resistor CalculatorCalculate SMD Resistance Power CalculatorCalculate Power in a circuit Voltage Divider CircuitCalculate voltage in Divider circuit Series Parallel CalculatorCalculate series parallel resistance Frequency CalculatorCalculate frequency