4 Replies Latest reply: Feb 9, 2013 10:35 PM by George Johnson
Chris Au Level 1 Level 1 (5 points)



I didn't know there were different wattages for the varoius models of notebooks.


At one office I work at, I bring my MBAir and plug it into my 27" Apple display; Ive been doing this daily for about 8 months now. Should I be concerned?


People at this office with different MBs share chargers all the time.


I have also been charging a 15" MBP with the MBA charger (45w).






  • Kappy Level 10 Level 10 (260,715 points)

    Keep in mind that the chargers that come with any particular model are intended to be used only with that model. Given that you can use a higher wattage charger with a computer that comes with a lower wattage charger, but not the other way around.


    So the 85 watt charger for 15" MacBook Pros could be used to charge a 13" MacBook Pro or MacBook or MacBook Air provided they all used the same MagSafe connector. But the 45, 60, or 65 watt charges should not be used with a 15" MacBook Pro. These chargers cannot provide sufficient wattage. Although they can charge the battery they will take considerably more time to do so. Furthermore, if the computer undertakes tasks that run the CPU and GPU near their maximum levels, there will be problems because the battery acts as a supplemental power source when the computer is connected to AC because the chargers cannot supply sufficient power on their own.

  • Chris Au Level 1 Level 1 (5 points)

    Hi Kappy;


    Would I be correct in interpreting your answer that if I want a single adapter to use trouble-free with all MacBooks (with the same connector) I should buy the 85w? Interestingly enough, they are all the same price.



  • Kappy Level 10 Level 10 (260,715 points)

    Yes, you could do that, but it would be best to use the proper charger for each particular model.

  • George Johnson Level 2 Level 2 (265 points)

    That should work just fine. The only disadvantage is that the 85-watt charger is slightly heavier in weight.