Amps to VA Calculator
Convert current and voltage to apparent power in VA.
Interactive Electrical Calculator
Amps to VA Calculator
Convert current and voltage to apparent power in VA.
Result
Enter values and calculate.
About the Amps to VA Calculator
The Amps to VA Calculator handles converting between watts, amps, volts, kW, kVA and VA without needing a spreadsheet, app download or manual lookup table. Convert current and voltage to apparent power in VA. 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 built for 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, and every field updates instantly so you can try a few scenarios before committing to a real installation.
How the calculation works
The calculator is built around this relationship:
VA = V × I; 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.
Every one of these values can be edited above, and the calculator updates the result the moment you press Calculate.
A worked example
For example, start with 10 A for current and 230 V for voltage. Press Calculate and the Amps to VA Calculator returns the result instantly — then change one field at a time to see how sensitive the answer is to that particular input.
When to use the Amps to VA Calculator
Typical reasons people reach for the Amps to VA 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 VA Calculator calculate?
Convert current and voltage to apparent power in VA.
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 VA Calculator runs entirely in your browser and is free to use.
What happens if I get this wrong?
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.
Will this work for both metric and everyday values?
The Amps to VA 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.