How Much Does 1,500 Watts Cost Per Hour? (Watts-to-Cost Quick Reference)

If you have ever looked at the back of an appliance, seen "1,500W" on the label, and wondered what that actually costs you, this page has the answer. Below is a quick reference table for the most common wattages, followed by the simple formula so you can calculate any wattage at your state's rate.

The Quick Answer

At the national average electricity rate of 17.98 cents per kWh:

• 100 watts costs about 1.8 cents per hour ($0.43/day, $13/month)
• 500 watts costs about 9.0 cents per hour ($2.17/day, $65/month)
• 1,000 watts costs about 18.1 cents per hour ($4.33/day, $130/month)
• 1,500 watts costs about 27.1 cents per hour ($6.50/day, $195/month)

Those assume continuous use. Most appliances cycle on and off, so your real cost is lower. Read on for the full table and the formula.

Watts-to-Cost Reference Table

All costs below use the national average residential electricity rate of 17.98 cents/kWh. For your state's exact rate, see electricity rates by state.

Important: The "Cost/Month" column assumes the appliance runs at full wattage for 8 hours every day. Most appliances do not run this way. A refrigerator is rated at 180W but cycles on and off, averaging about 60-80W over time. A space heater on a thermostat may cycle at 50-80% duty. Use the table as a ceiling estimate, then adjust for how your appliance actually runs.

The Formula (For Any Wattage)

The math behind every number in the table above:

Cost per hour = (Watts / 1,000) x Rate per kWh

That is it. Divide the wattage by 1,000 to convert to kilowatts, then multiply by your electricity rate. For example, at 17.98 cents/kWh:

• 1,500W / 1,000 = 1.5 kW
• 1.5 kW x $0.1798 = $0.270 per hour

To get the daily cost, multiply by hours used. To get the monthly cost, multiply the daily cost by 30.

For a calculator that does this automatically with your state's rate pre-loaded, use the electricity cost calculator.

How Your State Rate Changes the Cost

The table above uses the national average (17.98 cents/kWh), but rates vary by more than 3x across states. Here is what 1,500 watts per hour costs at different state rates:

The same 1,500W space heater costs $45/month in Louisiana and $144/month in Hawaii. The appliance is identical; only the rate changed. This is why knowing your state's rate matters more than knowing the wattage.

Common Wattage Questions Answered

"How much does it cost to run 1,500 watts for 24 hours?"

At the national average rate: 1,500W x 24 hours = 36 kWh x $0.1798 = $6.47 per day. Over a full month of 24/7 operation, that is $194. This is why leaving a space heater running all day adds up fast. Most 1,500W appliances (heaters, hair dryers, electric kettles) are not meant to run 24/7, but those that do (like a crypto mining rig) can produce $195+/month electricity bills.

"How much does 100 watts cost per month?"

At the national average rate: 100W running 24/7 = 72 kWh/month x $0.1798 = $12.95 per month. This is roughly what a 50-inch LED TV would cost if it ran around the clock. In practice, a TV running 5 hours/day at 100W costs about $2.70/month.

"How much does 1,000 watts cost per hour?"

At the national average rate: 1,000W / 1,000 = 1 kW x $0.1798 = $0.18 per hour (about 18 cents). This is a useful mental benchmark: 1,000 watts for 1 hour at the national average costs roughly 18 cents. Scale up or down from there.

"Is 1,500 watts a lot of electricity?"

For a portable appliance, yes. 1,500W is the maximum most appliances can draw from a standard 120V, 15A household outlet (1,800W is the technical max, but 1,500W is the safe continuous limit). Appliances at this wattage include space heaters, hair dryers, electric kettles, and air fryers. At 18 cents per hour, it is not expensive for short use (a kettle boils water in 3-4 minutes for less than a penny). It becomes expensive when it runs for hours, like a space heater running 8-12 hours per day.

"How do I find the wattage of my appliance?"

Check the label on the back or bottom of the appliance. It will list either watts (W) or amps (A) and volts (V). If it lists amps and volts, multiply them together to get watts: Amps x Volts = Watts. For example, 12.5A x 120V = 1,500W. If the label shows a range (e.g., 750-1,500W), that usually represents low and high settings.