Cost to Run a 30-watt tablet charger for 10 hours in Washington
Running a 30-watt tablet charger for 10 hours uses 0.3 kWh and costs $0.035 at $0.115/kWh in Washington. Do that every day and it adds up to $1.04 a month.
Calculate your own cost
- Per hour
- $0.0030.03 kWh
- Per day
- $0.0350.3 kWh
- Per week
- $0.2422.1 kWh
- Per month (30 days)
- $1.049 kWh
- Per year
- $12.59110 kWh
Formula: watts ÷ 1,000 × hours × rate. Edit any box and every number updates instantly.
People also ask
How much does a 30-watt tablet charger cost per hour?
At $0.115/kWh, it costs $0.003 per hour. The maths: 30 W ÷ 1,000 = 0.03 kWh per hour, × $0.115 = $0.003.
How much does it cost per month?
Used 10 hours a day for 30 days, it costs about $1.04 per month and uses 9 kWh. Change the hours in the calculator above to match how you use it.
How many kWh does it use?
0.3 kWh per day, 9 kWh per month and 110 kWh per year at 10 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 the actual charging duration for a closer estimate. Check your bill for the exact rate and enter it above.
Does my electricity rate change the answer?
Yes, a lot. At 10¢ per kWh the monthly cost is $0.90 and at 30¢ it is $2.70. Find your rate on your bill (total cost ÷ kWh used) and type it into the calculator.
Cost by hours of use in Washington
| Used per day | Energy per day | Cost per day | Cost per month | Cost per year |
|---|---|---|---|---|
| 1 hour | 0.03 kWh | $0.003 | $0.104 | $1.26 |
| 2 hours | 0.06 kWh | $0.007 | $0.207 | $2.52 |
| 3 hours | 0.09 kWh | $0.01 | $0.311 | $3.78 |
| 4 hours | 0.12 kWh | $0.014 | $0.414 | $5.04 |
| 5 hours | 0.15 kWh | $0.017 | $0.518 | $6.30 |
| 6 hours | 0.18 kWh | $0.021 | $0.621 | $7.56 |
| 7 hours | 0.21 kWh | $0.024 | $0.725 | $8.81 |
| 8 hours | 0.24 kWh | $0.028 | $0.828 | $10.07 |
| 9 hours | 0.27 kWh | $0.031 | $0.932 | $11.33 |
| 10 hours | 0.3 kWh | $0.035 | $1.04 | $12.59 |
| 11 hours | 0.33 kWh | $0.038 | $1.14 | $13.85 |
| 12 hours | 0.36 kWh | $0.041 | $1.24 | $15.11 |
| 13 hours | 0.39 kWh | $0.045 | $1.35 | $16.37 |
| 14 hours | 0.42 kWh | $0.048 | $1.45 | $17.63 |
| 15 hours | 0.45 kWh | $0.052 | $1.55 | $18.89 |
| 16 hours | 0.48 kWh | $0.055 | $1.66 | $20.15 |
| 17 hours | 0.51 kWh | $0.059 | $1.76 | $21.41 |
| 18 hours | 0.54 kWh | $0.062 | $1.86 | $22.67 |
| 19 hours | 0.57 kWh | $0.066 | $1.97 | $23.93 |
| 20 hours | 0.6 kWh | $0.069 | $2.07 | $25.19 |
| 21 hours | 0.63 kWh | $0.072 | $2.17 | $26.44 |
| 22 hours | 0.66 kWh | $0.076 | $2.28 | $27.70 |
| 23 hours | 0.69 kWh | $0.079 | $2.38 | $28.96 |
| 24 hours | 0.72 kWh | $0.083 | $2.48 | $30.22 |
How we worked it out
- Energy per hour: 30 W ÷ 1,000 = 0.03 kWh
- Cost per hour: 0.03 kWh × $0.115 = $0.003
- Cost per day: × 10 hours = $0.035
- Month and year: × 30 days = $1.04, × 365 days = $12.59
Washington electricity prices
Washington pays about $0.115 per kWh, which is 34% lower than the US average of $0.175. The same tablet charger would cost $1.58 a month at the national average.
What it costs in different places
Same 30-watt tablet charger, 10 hours a day. Only the local electricity rate changes.
| Place | Rate per kWh | Cost per month |
|---|---|---|
| United States | $0.175 | $1.58 |
| California | $0.32 | $2.88 |
| Texas | $0.155 | $1.40 |
| New York | $0.25 | $2.25 |
| Florida | $0.155 | $1.40 |
| Illinois | $0.17 | $1.53 |
| Pennsylvania | $0.18 | $1.62 |
| Ohio | $0.17 | $1.53 |
| Washington | $0.115 | $1.04 |
About tablet charger running costs
Tablet charging power changes as the battery fills and depends on the adapter and device. The maximum charger rating is not the average.
Typical sizes: 10 W, 20 W, 30 W, 45 W.
How to spend less: Use the actual charging duration for a closer estimate.
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 Washington. 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.