Plug-in electricity usage monitor
Plugs in between the wall and any single appliance to show its real, measured electricity use instead of an estimate.
Compare on AmazonWhat Does It Cost to Run That?
Ten common household appliances, priced per day, month, and year at the national average electricity rate — or your own rate if you know it.
Choose an appliance
Dehumidifier
300–700W typical
Window air conditioner
500–1500W typical
Portable air conditioner
800–1500W typical
Air purifier
30–100W typical
Portable space heater
750–1500W typical
Mini fridge
50–100W typical
Chest or upright freezer
100–400W typical
Electric clothes dryer
1800–5000W typical
Electric blanket
100–200W typical
Box fan
50–100W typical
EV charger (Level 2, 240V)
3800–11500W typical
Electric water heater (standard tank)
1500–4500W typical
The formula
kWh/day = watts ÷ 1000 × hours/day
Cost/day = kWh/day × (rate ÷ 100)
Tools and supplies to consider
These links go to an Amazon search so you can compare current options and prices.
Door and window weatherstripping kit
Seals air leaks around doors and windows, which reduces how hard heating and cooling appliances have to work.
Compare on AmazonReplacement air filter multipack
Keeps an air purifier, furnace, or window AC running efficiently instead of straining against a clogged filter.
Compare on AmazonIndoor hygrometer and thermometer
A humidity and temperature gauge that helps you judge whether a dehumidifier or heater actually needs to run.
Compare on AmazonMid-size dehumidifier
A mid-size dehumidifier for a basement or humid climate — check the capacity rating against your room size.
Compare on AmazonENERGY STAR window air conditioner
An ENERGY STAR-certified window air conditioner typically uses meaningfully less electricity per BTU than an older, uncertified unit.
Compare on AmazonFrequently asked questions
Why does this differ from my actual utility bill?
Nameplate wattage is often a maximum, not a constant draw. Cycling appliances like fridges and freezers, your exact usage pattern, and your utility's rate structure can all shift the real number.
Where do I find my appliance's actual wattage?
Check the nameplate or label on the unit itself, usually on the back or bottom, or the manufacturer spec sheet.
Should I use a plug-in energy monitor instead of estimating?
If you want an exact figure rather than an estimate, yes — a plug-in monitor measures actual draw over time, which accounts for cycling and real usage patterns an estimate cannot.
Does time-of-use electricity pricing change this?
Yes, if your utility charges different rates by time of day, your actual cost can differ from a flat-rate estimate — check your specific rate plan.