Joshua Morganstein wrote: I've been using an 87W adapter for several hours with my 16' and, as to be expected, it appears to work reasonably well charging the battery, though I assume a bit less swiftly than I could expect from a 96W adapter. If anyone has done or is aware of any testing that has been done to indicate my above understanding is incorrect, I would welcome any resource/links to learn more so I can better understand this issue. Based on all the constructive feedback on this thread and from what I've read elsewhere, it's my understanding that using a lower wattage rated adapter to charge a MacBook Pro internal battery does not increase the risk of any acute damage to the battery or computer, nor does it alter the life expectancy of the battery, which is largely impacted by charge cycles. However, I anticipate that would likely be under not just a heavy load, but one that is sustained for an extended period of time as the 87W adapter is supplying a fair amount of charge at all times. If I had the 16' under heavy load, I also imagine it's possible that the 87W adapter wouldn't be able to supply enough power to keep the battery from being drained, though probably very slowly. I've been using an 87W adapter for several hours with my 16' and, as to be expected, it appears to work reasonably well charging the battery, though I assume a bit less swiftly than I could expect from a 96W adapter.

I appreciate the OPs question about simply using existing adapters (for the potential savings of time, money, and resources), and the thoughtful responses offered by some here to help those less knowledgable consider the pros and cons of various options. If I just did what was 'recommended' I'd be spending about $400 just buying new 96W power adapters to replace all my 87W power adapters and left with five 87W power adapters I'd need to spend time and energy selling or otherwise finding a use for. I have multiple adapters in different locations throughout my home and work spaces at which I previously charged a 15' that I just replaced with a 16'.

87 macbook pro usb c charger