Apple 96W USB-C Power Adapter on a MacBook Air: Measured
Apple's 96W USB-C adapter measured on a MacBook Air M5: a 94 W contract at 4.7 A, and the same adapter dropping to 60 W on a cable without an e-marker chip.
Apple’s 96W USB-C power adapter, tested against a MacBook Air M5 with a low battery, per the methodology. This one was measured twice, on two different cables, because the cable turned out to matter more than anything about the charger.
With a 5 A e-marked cable
| Rated | 96 W |
| Negotiated | 94 W (20 V up to 4.7 A) |
| Live draw | 67.3 W (19.8 V at 3.39 A) |
| Protocol | USB PD 3.0 |
Profile menu: 15 W (5 V/3 A), 27 W (9 V/3 A), 45 W (15 V/3 A), 94 W (20 V/4.7 A - active).
Contract is not draw
Those two numbers sit at very different values, and the difference is the single most useful idea in this whole series.
94 W is the contract - the ceiling the charger and the Mac agreed on. 67.3 W is the live draw - what the machine happened to be pulling at that instant. The draw moves continuously: it depends on how empty the battery is, what the CPU is doing, whether the display is bright. The contract stays put.
A MacBook Air will rarely sustain 94 W, because it doesn’t need to. That isn’t the adapter failing to deliver, and it isn’t a cap being enforced - it’s headroom. The adapter is simply never the bottleneck.
This is exactly why a number printed on a box tells you so little, and why watching the negotiated contract separately from the live draw tells you so much.
With a non-e-marked cable
Same adapter, same Mac, same port. Only the cable changed - to Apple’s own 60W woven charge cable, which has no e-marker chip:
| Negotiated | 60 W (20 V up to 3 A) |
| Live draw | 67.3 W momentary, settling to the 60 W contract |
Profile menu: 15 W, 27 W, 45 W, 60 W (20 V/3 A - active), and then this line:
96 W (20.6 V up to 4.7 A) - Requires 5A Cable
The adapter didn’t change. A USB-C cable without an e-marker chip is limited to 3 A, and 20 V × 3 A = 60 W. That is a hard ceiling imposed by the wire, and it has nothing to do with the charger at all.
USB Connection Information shows the profile the adapter would offer and names the reason it can’t - so the missing 34 W is diagnosable rather than mysterious. If your Mac charges quickly on one cable and slowly on another, this is almost always why.
The cables
- The full 94 W needs a 5 A e-marked cable, such as the Apple 240W USB-C Woven Charge Cable (2 m).
- The 60 W result above was measured on the Apple 60W USB-C Woven Charge Cable (1 m) - a perfectly good cable that is simply not rated for 5 A.
Both are genuine Apple cables. Neither is defective. They are rated for different currents, and that rating decides your charging speed far more than the adapter does. See USB-C 100W vs 240W Cables and E-Marker Chips Explained.
Buying one
The Apple 96W USB-C Power Adapter is more adapter than a MacBook Air needs - which is the point, if you also charge a larger MacBook Pro. Pair it with a 5 A cable or you have bought a 60 W adapter.
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