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How Many kWh Does a Smartphone Charger Use?

Smartphone Charger energy cost calculator — see your exact daily, monthly, and yearly electricity cost.

Rate — MAY 2026 ⚡ 15W typical
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$

US national average. Edit for your local rate.

Daily Energy Use

0.03

kWh / day

Monthly Cost

$0.17

Yearly Cost

$2.02

Smartphone Charger — Cost Breakdown

Period kWh Used Cost ($)
Per Hour 0.0150 $0.0028
Per Day 0.03 $0.01
Per Month (30 days) 0.90 $0.17
Per Year (365 days) 10.95 $2.02
Real-World Comparison

Charging a smartphone uses about the same energy as running an LED bulb for 3 hours.

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3 Ways to Cut Your Smartphone Charger Energy Bill

  • 🌱

    Unplug the charger from the wall when not charging — even idle chargers draw 0.1–0.5W continuously.

  • 💡

    Charge to 80% instead of 100% — the last 20% is slower and less efficient, drawing the same wattage for longer.

  • Use the manufacturer's charger or a certified one — cheap chargers can be less efficient, wasting up to 30% as heat.

Startup Surge Information

Smartphone chargers are solid-state devices drawing consistent, low wattage with no surge.

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