Electronics Calculators

Calculate common electronics values such as Ohms law, voltage divider output, LED resistor values, battery life, RC/RL filters, and reactance.

Ohms Law Calculator

Calculate voltage, current, resistance, and power from any two known values.

LED Resistor Calculator

Calculate the series resistor needed for an LED circuit.

Voltage Divider Calculator

Calculate voltage divider output from Vin, R1, and R2.

Battery Life Calculator

Estimate battery runtime from capacity and current draw.

Resistor Color Code Calculator

Calculate 4-band resistor value and tolerance from colors.

Capacitance Converter

Convert capacitance values between pF, nF, µF, mF, and F.

Series and Parallel Resistor Calculator

Calculate the equivalent resistance of multiple resistors connected in series or parallel.

Filter Calculator

Calculate the cutoff frequency of RC and RL low-pass or high-pass filters using resistor, capacitor, and inductor values.

AWG Wire Size Converter

Convert AWG wire gauge to diameter, area, resistance per meter, and reference ampacity.

dBm to Watt Converter

Convert RF power values between dBm, mW, and W.

Frequency Wavelength Converter

Convert frequency and wavelength using the vacuum/air reference speed.

RC Time Constant Calculator

Calculate the RC time constant from resistor and capacitor values.

Reactance Calculator

Calculate capacitive or inductive reactance from frequency and component values.