How to find an appliance’s wattage

Good cost estimates begin with the right power figure. The label is the starting point, but it is not always the whole story.

Start with the nameplate

Look on the back, underside, door frame, power supply, or plug label. Use input watts when shown. Do not confuse output watts, cooling BTU, or motor horsepower with electrical input.

Convert volts and amps

When a label shows volts and amps but not watts, volts × amps gives an upper planning estimate for many simple loads. Motors and electronics can have power factors or cycling behavior that make measured use lower.

Measure when it matters

A plug-in energy meter can capture both watts and kWh over time for compatible 120 V appliances. For hardwired or high-voltage equipment, use manufacturer data or a qualified electrician rather than improvising a measurement.

Use the numbers

Apply this guide with one of WattMeasure’s free calculators. Results are planning estimates and should be verified for consequential decisions.

Last reviewed August 6, 2026