Cost to Run a 400-watt appliance for 20 hours in Texas
Running a 400-watt appliance for 20 hours uses 8 kWh and costs $1.24 at $0.155/kWh in Texas. Do that every day and it adds up to $37.20 a month.
Calculate your own cost
- Per hour
- $0.0620.4 kWh
- Per day
- $1.248 kWh
- Per week
- $8.6856 kWh
- Per month (30 days)
- $37.20240 kWh
- Per year
- $452.602,920 kWh
Formula: watts ÷ 1,000 × hours × rate. Edit any box and every number updates instantly.
People also ask
How much does a 400-watt appliance cost per hour?
At $0.155/kWh, it costs $0.062 per hour. The maths: 400 W ÷ 1,000 = 0.4 kWh per hour, × $0.155 = $0.062.
How much does it cost per month?
Used 20 hours a day for 30 days, it costs about $37.20 per month and uses 240 kWh. Change the hours in the calculator above to match how you use it.
How many kWh does it use?
8 kWh per day, 240 kWh per month and 2,920 kWh per year at 20 hours a day. A kWh is one kilowatt (1,000 W) used for one hour. It is the unit on your electricity bill.
How can I lower the cost?
Use it for fewer hours, switch to a lower-wattage model, and check whether your utility offers cheaper off-peak rates. Enter your own rate above to see the effect.
Does my electricity rate change the answer?
Yes, a lot. At 10¢ per kWh the monthly cost is $24.00 and at 30¢ it is $72.00. Find your rate on your bill (total cost ÷ kWh used) and type it into the calculator.
Cost by hours of use in Texas
| Used per day | Energy per day | Cost per day | Cost per month | Cost per year |
|---|---|---|---|---|
| 1 hour | 0.4 kWh | $0.062 | $1.86 | $22.63 |
| 2 hours | 0.8 kWh | $0.124 | $3.72 | $45.26 |
| 3 hours | 1.2 kWh | $0.186 | $5.58 | $67.89 |
| 4 hours | 1.6 kWh | $0.248 | $7.44 | $90.52 |
| 5 hours | 2 kWh | $0.31 | $9.30 | $113.15 |
| 6 hours | 2.4 kWh | $0.372 | $11.16 | $135.78 |
| 7 hours | 2.8 kWh | $0.434 | $13.02 | $158.41 |
| 8 hours | 3.2 kWh | $0.496 | $14.88 | $181.04 |
| 9 hours | 3.6 kWh | $0.558 | $16.74 | $203.67 |
| 10 hours | 4 kWh | $0.62 | $18.60 | $226.30 |
| 11 hours | 4.4 kWh | $0.682 | $20.46 | $248.93 |
| 12 hours | 4.8 kWh | $0.744 | $22.32 | $271.56 |
| 13 hours | 5.2 kWh | $0.806 | $24.18 | $294.19 |
| 14 hours | 5.6 kWh | $0.868 | $26.04 | $316.82 |
| 15 hours | 6 kWh | $0.93 | $27.90 | $339.45 |
| 16 hours | 6.4 kWh | $0.992 | $29.76 | $362.08 |
| 17 hours | 6.8 kWh | $1.05 | $31.62 | $384.71 |
| 18 hours | 7.2 kWh | $1.12 | $33.48 | $407.34 |
| 19 hours | 7.6 kWh | $1.18 | $35.34 | $429.97 |
| 20 hours | 8 kWh | $1.24 | $37.20 | $452.60 |
| 21 hours | 8.4 kWh | $1.30 | $39.06 | $475.23 |
| 22 hours | 8.8 kWh | $1.36 | $40.92 | $497.86 |
| 23 hours | 9.2 kWh | $1.43 | $42.78 | $520.49 |
| 24 hours | 9.6 kWh | $1.49 | $44.64 | $543.12 |
How we worked it out
- Energy per hour: 400 W ÷ 1,000 = 0.4 kWh
- Cost per hour: 0.4 kWh × $0.155 = $0.062
- Cost per day: × 20 hours = $1.24
- Month and year: × 30 days = $37.20, × 365 days = $452.60
Texas electricity prices
Texas pays about $0.155 per kWh, which is 11% lower than the US average of $0.175. The same appliance would cost $42.00 a month at the national average.
What it costs in different places
Same 400-watt appliance, 20 hours a day. Only the local electricity rate changes.
| Place | Rate per kWh | Cost per month |
|---|---|---|
| United States | $0.175 | $42.00 |
| California | $0.32 | $76.80 |
| Texas | $0.155 | $37.20 |
| New York | $0.25 | $60.00 |
| Florida | $0.155 | $37.20 |
| Illinois | $0.17 | $40.80 |
| Pennsylvania | $0.18 | $43.20 |
| Ohio | $0.17 | $40.80 |
| Washington | $0.115 | $27.60 |
What this estimate assumes
- The appliance draws its full stated wattage the whole time it is on. Real units with a thermostat cycle off and cost less.
- Wattage is the typical label value, not a measured value. Check the label on your own appliance.
- The rate is an approximate residential average in Texas. Your bill may include fixed fees, tiers or time-of-use pricing. Edit the rate above.
- A month is 30 days and a year is 365 days.