Watts to VA Calculator

To use the watts to VA calculator, simply enter the watts and power factor values and click the “Calculate” button to get the result in watts.

VA to watts calculator ►

Watts to VA calculation

The apparent power S in volt-amps (VA) is equal to the real power P in watts (W), divided by the power factor PF:

S_(VA) =  P_(W) / PF

Examples

1) Suppose you have an electrical device that has a power rating of 1000 watts and a power factor of 0.8. To convert the power from watts to VA, you can use the following formula:

VA = watts / power factor

So, in this case, the VA would be:

VA = 1000 / 0.8 = 1250

2) Now suppose you have another electrical device that has a power rating of 800 watts and a power factor of 0.95. Using the same formula as before, the VA can be calculated as follows:

VA = watts / power factor

VA = 800 / 0.95 = 842.1

Therefore, the device would require an 842.1 VA power supply to operate at its rated power with a power factor of 0.95.

Watts to VA Conversion Table for a Computer Power Supply

Here’s an example of a Watts to VA conversion table for a computer power supply:

Watts (W)	Volt-Amps (VA)
50	62.5
100	125
150	187.5
200	250
250	312.5
300	375
350	437.5
400	500
450	562.5
500	625
550	687.5
600	750
650	812.5
700	875
750	937.5

Note that these values are based on a power factor of 0.8, which is typical for computer power supplies.

Typical Power Factor of Common Household Electronics

Here’s a table showing typical power factor of common household electronics:

Electronic Device	Typical Power Factor
Incandescent light bulb	1.0
LED light bulb	0.7 – 0.9
Compact fluorescent bulb	0.5 – 0.7
Television	0.7 – 0.9
Desktop computer	0.6 – 0.8
Laptop computer	0.7 – 0.9
Printer	0.6 – 0.8
Microwave oven	0.6 – 0.8
Toaster	0.6 – 0.8
Vacuum cleaner	0.6 – 0.8
Refrigerator	0.6 – 0.8
Air conditioner	0.7 – 0.9
Ceiling fan	0.95 – 1.0

Note that these values are just approximate and may vary depending on the specific model and brand of the electronic device.

See Also