Save your math brain. Use our interactive tools to calculate resistor values, voltage drops, and frequencies.
Never fry an LED again. Input your source voltage, LED forward voltage, and desired current to find the exact resistor you need.
Open CalculatorDecode 4-band resistor color codes instantly, or input a resistance value to see what colors to look for.
Open CalculatorThe foundational math of all electronics. Calculate Voltage, Current, Resistance, or Power.
Open CalculatorReading a 5V sensor on a 3.3V ESP32? Calculate the exact R1 and R2 values needed to safely step down your voltage.
Open CalculatorDesign blinking LEDs and synthesizers! Calculate the frequency and duty cycle of a 555 timer in astable mode.
Open CalculatorBuilding audio circuits or smoothing PWM? Find the -3dB cutoff frequency for Low-Pass and High-Pass RC filters.
Open CalculatorFind the exact microsecond delays needed in your code to drive a stepper motor at your target RPM.
Open CalculatorCalculate how long your IoT project will run on a battery by factoring in active and deep sleep duty cycles.
Open CalculatorDesign safe PCBs. Calculate the minimum trace width required to carry a specific current without overheating.
Open CalculatorConvert raw analogRead() values from your Arduino or ESP32 back into real-world voltages.
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