A smartphone charger uses 10 watts running, 0 watts surge, with 100% duty cycle while charging.
Quick Answer Box:
- Running Watts: 10W
- Starting / Surge Watts: 0W
- Running Amps: 0.08A @ 120V
- Duty Cycle: 100%
- Daily kWh if charging 3 hours: 0.03 kWh
A standard 5W charger and a 10W charger both exist, but 10W is the average for a modern USB charger charging a phone from 20% to 80%.
How Much Does It Cost to Run a Smartphone Charger?
Formula: Watts x hours / 1000 x $/kWh = cost
At $0.15/kWh, 8 hours a day is an overestimate – most phones charge 2-3 hours:
| Usage | kWh per Day | Cost per Day @ $0.15 | Cost per Month @ $0.15 | Cost per Month @ $0.30 |
|---|---|---|---|---|
| 3 hrs/day | 0.03 kWh | $0.0045 | $0.13 | $0.27 |
| 8 hrs/day | 0.08 kWh | $0.012 | $0.36 | $0.72 |
| 24 hrs/day plugged in idle | 0.012 kWh* | $0.0018 | $0.05 | $0.11 |
*Idle draw when not charging a phone is about 0.5W.
At $0.45/kWh in California, 3 hours a day costs $0.41 per month. It is the cheapest device in your house to run.
Can a Portable Power Station Run a Smartphone Charger?
Yes. Any power station can run a 10W charger with no surge.
Here are 22 stations that can run it and how long:
Small – Under 500Wh:
- MARBERO Portable Power Station 88Wh – 88wh, 80w – 7.5hrs
- Jackery Explorer 300 – 293wh, 300w – 24.9hrs – about 12 full phone charges
- Azocek DC 18V to AC 110V Portable Power Station – 220wh, 220w – 18.7hrs
- BLUETTI AC50B – 448wh, 700w – 38.1hrs
- EcoFlow River 3 Plus Extra Battery EB600 – 572wh, 600w – 48.6hrs
Medium – Best for phones + laptop:
- Anker SOLIX C1000 – 1056wh, 1800w – 89.8hrs
- Anker SOLIX C1000 Gen 2 – 1056wh, 2000w – 89.8hrs
- BLUETTI AC70 – 768wh, 1000w – 65.3hrs
- EcoFlow DELTA 3 Plus – 1536wh, 1800w – 130.6hrs
- BLUETTI Elite 200 V2 – 2073.6wh, 2200w – 176.3hrs
- BLUETTI AC200L – 2048wh, 2400w – 174.1hrs
- EcoFlow DELTA 2 Max – 2048wh, 2400w – 174.1hrs
- OUPES Exodus 2400 – 2232wh, 2400w – 189.7hrs
- Dabbsson 2150Wh Portable Power Station – 2150wh, 2400w – 182.8hrs
Large – Home backup:
- Jackery Explorer 2000 v2 – 2042wh, 2200w – 173.6hrs
- BLUETTI Elite 300 – 3014wh, 2400w – 256.2hrs
- Anker SOLIX F3000 – 3072wh, 3600w – 261.1hrs
- EcoFlow DELTA Pro – 3600wh, 3600w – 306hrs
- PowerSmart 4800W Portable Inverter Generator – 13034wh, 3800w – 1107.9hrs
- Westinghouse 5000 Peak Watt Super Quiet Portable Inverter Generator – 19000wh, 3900w – 1615hrs
- Westinghouse 12500 Watt Dual Fuel Home Backup Portable Generator – 28000wh, 9500w – 2380hrs
- Westinghouse 14500 Peak Watt Tri-Fuel Home Backup Portable Generator – 35000wh, 11500w – 2975hrs
Runtimes are for the 10W wall adapter alone at 85% inverter efficiency. A phone battery holds about 15Wh, so divide runtime hours by 2 to get approximate number of full phone charges.
What Size Generator Do You Need for a Smartphone Charger?
Minimum 80W. Your surge is 0W, so any station that can do 10W continuous will run it. The MARBERO Portable Power Station 88Wh at 80W is already enough for 7.5 hours.
Recommendation: 100W – 300W. A Jackery Explorer 300 at 300W gives you 24.9 hours of charging and is quiet indoors. You do not need a gas generator for a phone charger.
2 Tips to Save Power on a Smartphone Charger Only
1. Use the USB port directly, not the AC brick. Plugging your iPhone AC brick into the AC outlet of the Anker C1000 wastes 15% in the brick and 15% in the inverter. The BLUETTI AC70 and Anker SOLIX C1000 Gen 2 have USB-C PD ports at 12V directly. Using USB-C PD from the station to your phone gives you 89.8 hours to 104 hours instead of 89.8 hours – you gain about 15% more charges, and the station fan stays off.
2. Turn on airplane mode while charging on a small station. A phone charging while using WiFi and GPS pulls 10W for the brick plus 5W for the phone radio – total 15W. On the MARBERO 88Wh, that drops runtime from 7.5 hours to 5.0 hours. Switching the phone to airplane mode drops total draw back to 10W and saves 2.5 hours of station capacity. For a fast charge, this matters on the Jackery 300 – 24.9 hours becomes 16.6 hours if you leave 5G streaming on while charging.
FAQ
How long will a smartphone charger run on Jackery Explorer 300?
24.9 hours for the charger alone. In real use, a phone charges 0 to 100% in about 2 hours at 10W, so the Jackery Explorer 300 at 293Wh, 300W will give you about 12 full iPhone charges before empty.
Does a fast charger need more watts?
Yes. This page is for a standard 10W charger. A fast charger labeled 25W uses 25W running and will cut all runtimes above by 2.5x. A 25W fast charger on a Jackery Explorer 300 runs 9.9 hours instead of 24.9 hours. Check your brick label – if it says Output 5V 3A or 9V 2.77A, it is 15W to 25W, not 10W.