electronics · 15W typical
Running a tablet charger costs about $0.09/month.
That's the typical tablet charger at 15W, run 4 hours a day at the US-average rate of 16.5¢/kWh. Change any of those and the number moves — use the calculator below to see yours.
Estimated cost
A tablet charger draws full power only while the thermostat/compressor is running — about 1.2 effective hours at 15W across your 4-hour window.
How you use it
Cost shifts with how long it's on.
The same tablet charger can cost very different amounts depending on usage patterns. Three common scenarios, at the US-average rate.
overnight charge
$0.09
per month
tablet charging overnight
daily top-off
$0.03
per month
casual daytime use
Where you live
$0.16 spread between the cheapest and priciest states.
Same appliance, same hours of use, different zip code — the monthly cost varies this much.
| State | Rate | Monthly | Yearly |
|---|---|---|---|
| Hawaii | 41.2¢ | $0.22 | $2.71 |
| California | 31.4¢ | $0.17 | $2.06 |
| Massachusetts | 30.8¢ | $0.17 | $2.02 |
| Connecticut | 28.7¢ | $0.15 | $1.89 |
| Rhode Island | 27.9¢ | $0.15 | $1.83 |
| New Hampshire | 24.6¢ | $0.13 | $1.62 |
| Alaska | 24.3¢ | $0.13 | $1.60 |
| New York | 22.3¢ | $0.12 | $1.47 |
| Maine | 22.1¢ | $0.12 | $1.45 |
| Vermont | 21.5¢ | $0.12 | $1.41 |
| Michigan | 19.3¢ | $0.10 | $1.27 |
| New Jersey | 19.1¢ | $0.10 | $1.25 |
| Maryland | 18.4¢ | $0.10 | $1.21 |
| Pennsylvania | 18.1¢ | $0.10 | $1.19 |
| District of Columbia | 17.8¢ | $0.10 | $1.17 |
| Wisconsin | 17.4¢ | $0.09 | $1.14 |
| Delaware | 17.2¢ | $0.09 | $1.13 |
| Illinois | 16.9¢ | $0.09 | $1.11 |
| Ohio | 16.6¢ | $0.09 | $1.09 |
| Nevada | 16.3¢ | $0.09 | $1.07 |
| Indiana | 15.8¢ | $0.09 | $1.04 |
| Virginia | 15.7¢ | $0.08 | $1.03 |
| Minnesota | 15.6¢ | $0.08 | $1.02 |
| Colorado | 15.4¢ | $0.08 | $1.01 |
| Alabama | 15.2¢ | $0.08 | $1.00 |
| West Virginia | 15.2¢ | $0.08 | $1.00 |
| Florida | 15.1¢ | $0.08 | $0.99 |
| New Mexico | 14.8¢ | $0.08 | $0.97 |
| Texas | 14.8¢ | $0.08 | $0.97 |
| Arizona | 14.7¢ | $0.08 | $0.97 |
| South Carolina | 14.7¢ | $0.08 | $0.97 |
| Kansas | 14.6¢ | $0.08 | $0.96 |
| Georgia | 14.2¢ | $0.08 | $0.93 |
| Iowa | 14.1¢ | $0.08 | $0.93 |
| North Carolina | 13.9¢ | $0.08 | $0.91 |
| Missouri | 13.6¢ | $0.07 | $0.89 |
| Oregon | 13.4¢ | $0.07 | $0.88 |
| Tennessee | 13.3¢ | $0.07 | $0.87 |
| Kentucky | 13.2¢ | $0.07 | $0.87 |
| Mississippi | 13.1¢ | $0.07 | $0.86 |
| Oklahoma | 13.1¢ | $0.07 | $0.86 |
| South Dakota | 12.7¢ | $0.07 | $0.83 |
| Montana | 12.4¢ | $0.07 | $0.81 |
| Nebraska | 12.2¢ | $0.07 | $0.80 |
| Arkansas | 12.1¢ | $0.07 | $0.79 |
| Washington | 12.1¢ | $0.07 | $0.79 |
| Louisiana | 11.9¢ | $0.06 | $0.78 |
| Wyoming | 11.6¢ | $0.06 | $0.76 |
| North Dakota | 11.5¢ | $0.06 | $0.76 |
| Utah | 11.4¢ | $0.06 | $0.75 |
| Idaho | 11.3¢ | $0.06 | $0.74 |
Efficient vs. inefficient
A $2.89/year difference across the wattage range.
Swapping a high-draw model for an efficient one pays for itself. Here's what that looks like annually at typical usage.
Most efficient
5W
$0.03 per month
$0.36 per year
Typical
15W
$0.09 per month
$1.08 per year
High draw
45W
$0.27 per month
$3.25 per year
When it hits hardest
year-round peak
Constant daily use.
Ways to cut the cost
- 1
Unplug when not charging — old chargers draw 1-3W idle
Saves 10-25 kWh/year
- 2
Use GaN chargers for near-zero idle draw
Negligible standby vs old blocks
- 3
Don't overcharge — lithium batteries don't benefit
Preserves battery life and saves tiny watts
Real-world wattages
Pulled from actual spec sheets.
| Brand | Model | Watts |
|---|---|---|
| Apple | 20W USB-C iPad Charger | 20W |
| Samsung | Tab S9 45W Charger | 45W |
| Anker | USB-C 30W Nano 3 | 30W |
Picks that actually move the needle
Three products worth comparing if you're thinking about upgrading or supplementing what you have.
Some links below are affiliate links. If you buy, we may earn a small commission — it never changes the price you pay, and we only recommend picks we would stand behind.
See also
Related appliances
Sources: www.energy.gov · www.energystar.gov
Last updated: 2026-04-13