Does my data get uploaded anywhere?
No. Everything runs locally in your browser and nothing is sent to a server.
Is this free to use?
Yes. It is completely free, with no account, no signup, and no usage limits.
Does it work on a phone?
Yes. The page runs in any modern mobile browser, on iPhone and Android alike, with no app to install.
How do I convert kVA to kW?
Multiply by the power factor. kW equals kVA times PF, so 10 kVA at 0.8 PF is 8 kW. Without knowing the power factor of the load there is no conversion, which is why this page scales VA units only and leaves the PF step to you.
Why are UPS units rated in VA rather than watts?
Because the limiting factor is current, and the internal components heat with current regardless of the phase relationship. A UPS rated 1,500 VA can supply 1,500 VA of apparent power, and how many watts of real work that becomes depends on the power factor of what you plug in.
What size UPS do I need for a 600 W load?
Divide the watts by the power factor. At a typical modern power factor of 0.9, a 600 W load needs about 667 VA, so a 750 VA or 1,000 VA unit gives you margin. Buying by watts alone will undersize the unit.
How do I calculate apparent power in a three-phase system?
For a balanced three-phase load, S equals the square root of 3 times the line-to-line voltage times the line current. This page does not carry that factor, so compute S first and then use it to scale between VA, kVA and MVA.
What is the difference between VA and W?
VA is voltage times current with no regard to phase. W is the part of that which actually does work. They are equal only when voltage and current are in phase, which is to say at a power factor of 1. Any reactive load makes VA larger than W.