Phone / Laptop Charger
What size extension cord for a Phone / Laptop Charger?
A phone / laptop charger draws about 1 amps (120W) at 120V. To carry that safely you need at least 16 AWG copper, and even then only for short runs, up to roughly 200 ft before voltage drop and heat become a problem. Thinner cord (the common 16 AWG household type) can overheat under this load and is a fire risk.
Cord gauge by length for a phone / laptop charger
The longer the cord, the thicker it must be to keep voltage drop under 3% at 1A. Minimum recommended copper gauge by run length:
| Cord length | Minimum gauge | Notes |
|---|---|---|
| 25 ft | 16 AWG | Minimum safe gauge |
| 50 ft | 16 AWG | Minimum safe gauge |
| 100 ft | 16 AWG | Minimum safe gauge |
| 150 ft | 16 AWG | Minimum safe gauge |
Safety note
Low-power devices work fine with any standard extension cord. Indoor-rated 16 AWG is sufficient.
Why gauge matters
A smaller AWG number means thicker copper and lower resistance. Undersized cord drops voltage (making motors and heating elements work harder) and turns the lost energy into heat in the cord itself. At 1A, a too-thin or coiled cord can get hot enough to melt insulation. Always uncoil cords fully during use, and never chain two cords together for a high-draw phone / laptop charger.
Frequently asked questions
What gauge extension cord for a phone / laptop charger?
Use at least 16 AWG copper for a phone / laptop charger (1A). For runs longer than 200 ft, step up to the next thicker gauge to hold voltage drop under 3%.
How long can the extension cord be?
At 16 AWG, keep it to about 200 ft for a phone / laptop charger. Beyond that, use a thicker cord: see the gauge-by-length table above.
Can I use a regular 16 AWG cord?
No. A standard 16 AWG household cord is not rated for the 1A a phone / laptop charger draws and can overheat. Use 16 AWG or thicker, and ideally plug the phone / laptop charger directly into a wall outlet.
Disclaimer: For reference only. Consult a licensed professional.