Use this free kVA to amps calculator to estimate current from kilovolt-amps, voltage, and phase type for transformer, UPS, and generator planning.
25 kVA at 480 V (three-phase)
kVA is already apparent power, so no power factor input is needed here. Transformer, UPS, generator, breaker, and conductor sizing still need equipment instructions and qualified review.
Estimate transformer current from a kVA rating.
Check rough UPS or generator current before reading the full specification.
Compare single-phase and three-phase current for the same kVA rating.
Understand apparent power separately from real power.
Sanity-check an equipment label before asking for qualified electrical help.
Prepare a current estimate before using a voltage drop or load planning tool.
About 30.07 A
About 41.67 A
About 41.67 A
About 208.18 A
About 18.04 A
About 48.11 A
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Plain-language answers about when to use the tool, what it does with your inputs, what to double-check, and how privacy works.
Use it when your task matches one of these common needs: Estimate transformer current from a kVA rating. Check rough UPS or generator current before reading the full specification. It works best when you already know the measurements, amounts, units, or options the page asks for.
In plain language: VA = kVA x 1,000. Single-phase amps = VA / volts. Three-phase amps = VA / (volts x sqrt(3)). Use line-to-line voltage for balanced three-phase calculations. The examples on the page are there so you can compare your inputs with a worked example before copying the answer.
kVA: apparent power in kilovolt-amps. One kVA equals 1,000 volt-amps. Volts: the equipment voltage used in the current calculation, such as 120 V, 208 V, 240 V, 480 V, or 600 V. Phase: single-phase or three-phase formula selection. Line-to-line voltage: the voltage to use for a balanced three-phase kVA calculation. Amps: the estimated current after apparent power is divided by the voltage factor.
Read the headline answer, then check the supporting lines and examples to understand how the calculator got there. If one input changes, rerun the tool and compare the new answer instead of guessing.
This is a simplified apparent-power estimate for planning and comparison. Transformer, UPS, generator, breaker, conductor, motor-starting, derating, and code decisions still need equipment instructions and qualified electrical review. Also check the unit, scale, mode, and result limit because small input changes can change the answer.
First multiply kVA by 1,000 to get volt-amps. For single-phase systems, divide volt-amps by volts. For three-phase systems, divide volt-amps by volts times the square root of 3.
kVA is already apparent power. Power factor is used when converting between real power in kW and apparent power in kVA, not when turning kVA directly into amps.
Use amps = kVA x 1,000 / (volts x 1.732). The 1.732 is the square root of 3, and the voltage should be the line-to-line voltage for the three-phase system.
Not always. kW is real power and kVA is apparent power. They match only when power factor is 1, which is not true for many AC loads.
No. Use the result as planning math only. Real breaker, conductor, transformer, UPS, and generator sizing depends on code rules, nameplate instructions, continuous loads, derating, temperature, and qualified electrical review.
For a balanced three-phase kVA calculation, use line-to-line voltage, such as 208 V, 480 V, or 600 V. Mixing voltage types can change the amp estimate by a large amount.
No. The calculator runs in your browser tab. Your recent answers stay only on the page while you use it, and they are not sent to a server.