What wattage USB-C charger do I need?

Start with the power your device actually wants, then make sure the charger port and cable can both deliver at least that much.

The four numbers to compare

1. Device target: the wattage needed for the manufacturer's preferred or fast-charge behavior.
2. Charger total: the overall power budget of the charger.
3. Per-port maximum: a 100W charger may have a 65W USB-C port and a smaller secondary port.
4. Cable power rating: the cable can be the lowest ceiling in the chain.

A practical sizing rule

If your laptop targets 65W, buy a charger with a USB-C port rated for at least 65W and a cable rated for at least 65W. Choosing 100W can provide useful headroom for another device, but only if the charger supports a power split that leaves enough on the laptop port.

Can you use a larger charger?

Normally yes with standards-compliant USB Power Delivery equipment. USB PD is a negotiated system: a charger advertises available profiles and the device requests what it can accept. The charger rating is a maximum capability, not power forced into the device.

What about USB PD 3.1?

USB-IF says USB Power Delivery can support up to 240W with newer Extended Power Range operation. That does not mean every charger, cable or device supports 240W — all parts of the chain still need compatible ratings.

Check a charging setup →

Reviewed September 12, 2026. This guide explains power compatibility, not electrical repair or modification.