Electrical & Electronics Calculators

More Than a Calculators

Electrical & Electronics Calculators

Fast tools for electrical work and electronics: Ohm’s law, kW/kVA/amps, single-phase & three-phase power, voltage drop, wire sizing, resistor networks, RC timing, battery runtime, and energy costs.

Ohm’s Law & Basics

Core circuit math: voltage, current, resistance, and power.

Power: kW, kVA, VA, HP

Convert and estimate electrical power for devices, motors, and panels.

Single-Phase & Three-Phase

Dedicated calculators for 1-phase and 3-phase power, current, and kVA.

Wiring, Cable Size & Voltage Drop

Plan cable runs and reduce losses. Great for long distances and higher loads.

Energy (kWh) & Cost

Estimate energy usage and cost based on watts/kW and operating time.

Resistors, Dividers & LEDs

Common electronics helpers for resistance networks and LED circuits.

RC Timing & Filters

Time constants, cutoff frequency, and quick filter design helpers.

AC Signals (RMS / Peak)

Convert RMS ↔ peak and handle basic waveform values.

Electrical & Electronics Calculators FAQ

Short answers to the questions people ask most.

Which calculator should I start with?

Start with Ohm’s Law. For real work, the next most useful are kW↔Amps, kVA↔kW (PF), and Voltage Drop.

What’s the difference between kW and kVA?

kW is real (usable) power, kVA is apparent power. Power factor (PF) links them: kW = kVA × PF.

Why is three-phase current lower for the same kW?

Three-phase power uses the √3 factor and typically distributes power more efficiently, so current can be lower at the same power level.

How accurate are voltage drop estimates?

They’re accurate for the math, but real results depend on cable type, temperature, installation method, and actual load conditions.

Do these tools replace an electrician/engineer?

No. They’re for planning and checking. For safety-critical work, follow local codes and consult a qualified professional.

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