Apple 70W USB-C Power Adapter on a MacBook Air: Measured

Apple's 70W USB-C adapter measured on a MacBook Air: a 68 W contract at 3.4 A, requiring a 5A cable to deliver its full power.

Apple 70W USB-C Power Adapter, model A2743, front view with a single USB-C port.

Apple’s 70W USB-C power adapter, tested against a MacBook Air with a low battery, per the methodology.

Ratings label: Input 100-240V~ 1.8A 50-60Hz, EMC 8425. 70.0W 45.0W 27.0W 15.0W. USB PD Output 20.6V at 3.4A, or 15.0V at 3.0A, or 9.0V at 3.0A, or 5.0V at 3.0A. Salcomp Technologies India Private Limited. E135498.

The numbers

Rated70 W
Negotiated68 W (20 V up to 3.4 A)
Live draw65.1 W (19.8 V at 3.29 A)
ProtocolUSB PD 3.0

Profile menu: 15 W (5 V up to 3 A), 27 W (9 V up to 3 A), 45 W (15 V up to 3 A), 68 W (20 V up to 3.4 A).

A 5A cable requirement

The top 68 W profile negotiates at 3.4 A. Standard non-e-marked USB-C cables are hard-capped at exactly 3 A (which equals 60 W at 20 V).

Because this adapter’s top profile pushes past that limit at 3.4 A, it strictly requires a 5A (100W+) e-marked cable to negotiate its full advertised power. If you plug it in using a standard 3A cable, the charger will only advertise up to 60 W, and that’s all you’ll get.

70W USB-C Power Adapter. Designed by Apple in California, Assembled in India. Model A2743. TM and copyright 2023 Apple Inc.

Buying one

The Apple 70W USB-C Power Adapter delivers effectively its full rating to a MacBook Air, as long as you pair it with a 5A cable. A single-port brick that comfortably covers any Air or 14-inch Pro.

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