So 85 watt charger will not harm the Mac Book Air? I would not want to have to toss them out now that I have moved from Pro to Air models.

  • Asked about:  QA Apple MagSafe Power Adapter

11 Answers from the Community

  • Best Answer:

    Yes you can. It works, fine for mine. Since I have both Mac books. I am only using the 85w. You can use a higher watt to charge a lower watt item. Just you cannot use a lower watt for a higher item. Go read a few and they all agreed.

  • Yes, you can use the 85 Watt Power Supply (or 65 Watt) on the Macbook Air (Late 2010). I just spoke to Apple Support and they stated it was no problem. The MacBook Air would only draw what it needed from the more powerful Powersupplies. So if you already own a 65 or 85W, you can safely use it with the Air.

    You can however NOT use the 45 Watt with the MacBook Pro's. Rule of Thumb, any higher rated Powersupply can be used, but never use a lower watt Powersupply then what was supplied with your Macbook.

  • The 85 watt Magsafe Adapter has 100-240v 1.5A input, with 16.5-8.5 v output 4.6A max output .

    It will cover the Mac Air 45W requirement of 14.5V .

    The variable output voltage will cover any Mac operating between 16.5-8.5V and not excceeding the 4.6 A.

  • Official apple answer stating it is okay: look up the knowledge base on the apple support article: HT2346

  • I asked Apple via the live chat and they said using a higher rated adapter "would not be recommended" and would run the risk of messing up the battery or computer. I have read a million posts saying higher wattage is okay (because the computer will only draw what it needs), and I use an 85w adapter with a 60w MacBook all the time. However, the output voltage on the higher adapters says 18.5v, but the Air adapter is something like 14.5v.

    If the output voltage is actually variable, I have no way of knowing that from the side of the adapter. I would really like a definitive answer to this.

  • I was told not to use a higher watt charger on my MBA. Here's the chat transcript:

    Chadwick L: Hello, how are you today?
    You: Hi. Fine thanks. Can I use a 60w charger (MacBook) with my new MacBook Air. the Air came with a 45w charger.
    Chadwick L: You can, but it's not recommended because the 60W may overload the battery.
    You: i figured the MBA would just draw what it needs.
    Chadwick L: You would think, however it's actually the charger that decides how big of a charge the battery gets. The battery has not way of controlling how much it takes.

  • I just placed the 85-watt in service for my MBA and it worked fine. All three chargers - 85, 60, & 40 are the same price. I really don't understand why Apple has three products when they could simply market the single 85-watt for everything.

    I recently bought (and LOVE) my MBA. At some point I intend to get a 15" MBP. I bought the 85-watt yesterday to have power for my MBA in a second room without having to unplug & move the MBA charger cable if I want to hibernate for awhile in my back room. I got the 85-watt so I'll "already have a proper spare" when I get the MBP later.

    Also, I recommend NOT popping the charging cable off by the cable itself - disconnect the MagSafe by the CONNECTOR. Repeatedly jerking on the cable to disconnect the MagSafe is just asking for cable failure.

  • Kenneth is right, any Apple charger with enough wattage will do, according to the Apple Knowledge Base article HT2346 that he cites, which has been updated to include even the USB-C charger. The device will not charge any faster with a higher wattage charger, or charge more. Using a higher wattage charger with a lower wattage laptop is like using a light fixture that can support a 200 watt bulb with only a 75 Watt bulb. No problem.

  • The biggest concern generally is that a higher Voltage (the 18.5V) rating would damage a lower voltage rated item. This is a BIG BIG BIG no-no for electronics. Wattage is the amount of power being delivered (Volts * Amps) and while a lower wattage item might only draw a lower current (the Amps) it will be damaged by higher volts.

    With that being said, I believe Apples power adapters are smart and can downgrade their voltage supply on the higher rated adapters... so they should be ok in general.

    I hope that helps a little to clear it up. with third party adapters don't assume that they will be smart like that, you could damage your 13" or Air with a too high rated adapter.


  • DO NOT use any other charger than assigned to your Mac.

    i used the 60W on my MBA for a while (about 4 months) after i broke my original 45W charger. The battery life began to noticably decrease in performance within these couple of months. At the end of it, my MBA needed its battery serviced. Luckily, I had AppleCare.

  • the reason that apple dont recommend it is because they like to cover themselves.

    as long as the power supply doesnt over power the battery (eg on a normal (non mac) laptop using a 15v powersupply when it only wants a 10v) your laptop should be fine