Amps to kVA Calculator
Convert line current to apparent power in kVA.
Interactive Electrical Calculator
Amps to kVA Calculator
Convert line current to apparent power in kVA.
Result
Enter values and calculate.
About the Amps to kVA Calculator
Use the Amps to kVA Calculator below to work through converting between watts, amps, volts, kW, kVA and VA in seconds, right in your browser. Convert line current to apparent power in kVA. Equipment nameplates, breaker ratings, generator ratings and utility bills rarely all use the same unit, so converting correctly is a routine step in almost every electrical job.
It's aimed at electricians sizing breakers and cable, solar and generator installers matching equipment ratings, and anyone reading a nameplate that lists one unit when they need another, who need a fast, reliable number without redoing the math by hand each time.
How the calculation works
Behind the scenes, the calculation follows:
kVA = V × I / 1000; three phase multiplies by √3.
Where each input maps to a field in the calculator above:
- Current in A.
- Voltage in V.
- System — choose between DC, Single Phase, Three Phase.
You can adjust any of these values as many times as you like; the result updates on every change with nothing sent off your device.
A worked example
For example, start with 20 A for current and 400 V for voltage. That's a reasonable starting point to explore from: nudge one value up or down and watch how much the result shifts before you commit to a final design figure.
When to use the Amps to kVA Calculator
Typical reasons people reach for the Amps to kVA Calculator:
- Converting a nameplate wattage to the amp draw needed to size a breaker or extension cord.
- Turning a generator or UPS kVA rating into the real kW load it can actually support.
- Checking a utility bill or inverter spec sheet that mixes kW, kWh and kVA.
- Working out current draw for a three-phase motor or panel from its power rating.
Good practice: A typical inductive load (motors, transformers, some electronics) has a power factor below 1, which means its current draw is higher than a simple watts ÷ volts calculation suggests.
Also worth knowing: Always check whether the source rating is real power (W/kW) or apparent power (VA/kVA) before converting — they are only equal when power factor is exactly 1.
Frequently asked questions
What does the Amps to kVA Calculator calculate?
Convert line current to apparent power in kVA.
Can I rely on this number for a real installation?
The formula above is applied exactly to the values you enter, so the math itself is precise. Real-world results can still differ due to component tolerances, temperature, installation method, equipment efficiency and local code requirements, so treat the output as a strong planning estimate and verify final designs against manufacturer data and the electrical code that applies to your installation.
Do I need to sign up or install anything to use it?
No sign-up, download or installation is needed. The Amps to kVA Calculator runs entirely in your browser and is free to use.
What happens if I get this wrong?
Power factor and phase count both change the relationship between watts, volt-amps and current, which is where most manual conversion mistakes happen.
Can I use this on a phone, or does it need a desktop?
The Amps to kVA Calculator works on any modern browser, phone or desktop, and recalculates as soon as you press Calculate. If a result looks off, double-check that every field is filled in with the unit shown next to it (mixing up units, such as W with kW, is the most common cause of an unexpected answer) and re-enter the values.