Step 1
Look around the fan’s edge for printed data from the manufacturer. You usually find this around the certification emblems on the casing.
Step 2
Look for a number followed by “V” and one followed by “A.” These numbers represent the voltage and amperage of the fan. If you don’t find a number followed by a “V,” assume the number is 115 or 220, depending on the region of the world you live in. If you live in America, you use a 115 volt circuit. In Europe, you often use 220 volts.
Step 3
Multiply the two numbers. The result is the wattage of your fan. If you have a fan that reads 115V and 1.5A, then the fan uses 172.5 watts.