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How many watts does a light bulb use?

A light bulb draws 6–100 watts while running, which is 0.05–0.83 amps on a 120 V circuit.

Light bulb watts, amps and circuit

Typical power use of a light bulb
Running watts6–100 W
Voltage120 V
Running amps0.05–0.83 A
Circuitstandard 120 V outlet

Also called: led bulb, led light bulb, led light, lamp, 60 watt bulb, 100 watt bulb.

Light bulb watts by size and type

Running and starting watts of light bulb types
Size or typeRunning watts, WVolts, VAmps, AStarting watts, W
Light bulb6–1001200.05–0.83—
LED, 60 W equivalent6–101200.05–0.08—
LED, 100 W equivalent15–181200.12–0.15—
CFL, 60 W equivalent131200.11—
Halogen, 60 W equivalent42–431200.35–0.36—
Incandescent, 60 W601200.5—
Incandescent, 100 W1001200.83—
050100Watts, WSize or typeLight bulbLight bulb, Running watts: 5.9–1005.9–100LED, 60 WequivalentLED, 60 W equivalent, Running watts: 5.9–105.9–10LED, 100 WequivalentLED, 100 W equivalent, Running watts: 14.5–17.714.5–17.7CFL, 60 WequivalentCFL, 60 W equivalent, Running watts: 1313Halogen, 60 WequivalentHalogen, 60 W equivalent, Running watts: 42–4342–43Incandescent, 60 WIncandescent, 60 W, Running watts: 6060Incandescent, 100 WIncandescent, 100 W, Running watts: 100100020406080100Watts, WSize or typeLight bulbLight bulb, Running watts: 5.9–1005.9–100LED, 60 W equivalentLED, 60 W equivalent, Running watts: 5.9–105.9–10LED, 100 W equivalentLED, 100 W equivalent, Running watts: 14.5–17.714.5–17.7CFL, 60 W equivalentCFL, 60 W equivalent, Running watts: 1313Halogen, 60 W equivalentHalogen, 60 W equivalent, Running watts: 42–4342–43Incandescent, 60 WIncandescent, 60 W, Running watts: 6060Incandescent, 100 WIncandescent, 100 W, Running watts: 100100
Watts of light bulb types. The lighter part of a bar is the upper end of the typical range.

How long a portable power station runs a light bulb

Runtime of a light bulb on a portable power station, at 85% inverter efficiency
Battery capacity, WhAt 100 W, hAt 5.9 W, h
5004.372
1,0008.5144.1
2,00017288.1
3,60030.6518.6

A 500 Wh portable power station runs a light bulb drawing 100 W for about 4.3 hours at 85% inverter efficiency. Runtime = capacity × 85% ÷ watts; the 85% efficiency is an assumption. The power station's AC output must be at least 100 W.

What it costs to run a light bulb

Running a light bulb at 53 W, the middle of its 6–100 W range, for one hour a day uses 19.3 kWh a year. That costs about $3.48 a year at $0.18 per kWh, the US average residential price for August 2026.

W
h
$/kWh

Your bill's total ÷ kWh used. 0.18 is the US residential average.

Result
$0.29 / month
Per day
$0.01
Per year
$3.48
Energy per day
0.05 kWh
Energy per month
1.6 kWh

How it is calculated

  1. kWh per day = 53 W × 1 h ÷ 1,000 = 0.053
  2. Per month = 0.053 kWh × 30.4 days × $0.18 = $0.29

What affects light bulb power use

The "equivalent" number on an LED box is the old incandescent bulb it replaces, not what the LED draws. An LED gives the same light as a 60 W incandescent bulb at about 6 to 10 W. A lamp draws only what its bulbs draw.

How the amps are calculated

Amps = watts ÷ volts. For 100 W at 120 V that is 0.83 A. The 6–100 W range covers typical models; the nameplate on a light bulb gives the exact figure.

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