USB-C charger wattage explained: how many watts you need

The watt number on a charger is the most useful spec on the box. It tells you the maximum power the charger can deliver, not what every device will draw.

Match the charger to the device

Phones usually charge at 20 to 45 watts. Most thin laptops want 45 to 65 watts, and larger laptops can need 100 watts or more. Check your device's original charger or the maker's spec page for the number.

Power Delivery

USB Power Delivery (PD) lets the charger and device agree on a safe voltage. A higher-watt PD charger will not harm a phone; the phone simply takes what it needs.

Multi-port chargers

On chargers with two or more ports, the total wattage is shared. Look for the per-port numbers in the listing.

Quick checklist

• Total and per-port wattage
• USB PD support
• A cable rated for the wattage (100W or 240W for laptops)
• Safety certification marks listed by the maker