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How Many kWh Does a Laptop Use?

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

Rate — APRIL 2026 ⚡ 50W typical
1Enter Wattage
2Set Hours
3See Costs
$

US national average. Edit for your local rate.

Daily Energy Use

0.40

kWh / day

Monthly Cost

$2.26

Yearly Cost

$27.49

Laptop — Cost Breakdown

Period kWh Used Cost ($)
Per Hour 0.0500 $0.0094
Per Day 0.40 $0.08
Per Month (30 days) 12.00 $2.26
Per Year (365 days) 146.00 $27.49
Real-World Comparison

Running a laptop for a full 8-hour workday uses about the same energy as making 4 slices of toast.

3 Ways to Cut Your Laptop Energy Bill

  • 🌱

    Reduce screen brightness to 50% — the backlight is the single largest power consumer in a laptop.

  • 💡

    Use the battery saver mode even when plugged in to throttle background tasks and reduce CPU power draw.

  • Unplug external peripherals like USB drives and mice when not in use, as each draws a small continuous current.

Startup Surge Information

Laptops draw very stable wattage through their DC adapter, with no meaningful startup surge.