Can you charge a MacBook Air 15″ (M4) with a Google 30W USB-C?

Worked out from the manufacturers’ specifications. Have a different charger? Pick it below the answer.

Answer
Yes, but slowly

It charges, but at about 30 W — well below what the MacBook Air 15″ (M4) can take. Fine overnight or while idle; under heavy use the battery may still drain.

Power delivered30 W of 70 W max
0 Wfast: 70 W
0 → 50%
~59 min
0 → 100%
~2 h 40 min

Estimated from the manufacturer’s stated fast-charge time, with the device idle.

Try another charger

How long to 50% with each charger

Shorter bar is faster. The highlighted row is the charger on this page.

Want it faster?

Full speed needs 70 W or more. These chargers get there:

MacBook Air 15″ (M4) charging specs

Fast charging needs
70 W
Max input (approx.)
70 W
In the box
35W Dual
Battery
66.5 Wh
Google 30W USB-C
30 W · USB-C · PPS

Sources: Apple: MacBook Air (15-inch, M4, 2025) tech specs · Apple: Fast charge your MacBook Air or MacBook Pro · Google Store (UK): 30W USB-C Power Adapter. Checked 2026-10-17.

Quick answers

Is it safe to charge the MacBook Air 15″ (M4) with the Google 30W USB-C?

Yes. USB Power Delivery negotiates power, so the MacBook Air 15″ (M4) only takes what it can handle and the charger only gives what it can supply. A weaker charger is slower, not dangerous.

How many watts does the MacBook Air 15″ (M4) need for fast charging?

70 W or more. Fast-charge capable with the 70W USB-C Power Adapter.

How long does the MacBook Air 15″ (M4) take to charge with the Google 30W USB-C?

About 59 min to 50% and 2 h 40 min to full, estimated with the device idle.