Chosen Solution
so, I just got this MacBook Air 2018. not only it overheats very quickly, the battery drop is very significant. I use the MacBook from some light browsing using Safari, just for 30 minutes, and the brightness of only 40%, the battery drained about 6 to 7 percent. is that normal? because it’s like new and I rarely use this MacBook.
Best thing is to install this gem of an app CoconutBattery. It will allow you to monitor your battery usage. Take a snapshot of the main window and post it here for us to see as well Adding images to an existing question. Frankly, your system shouldn’t need a new battery yet as its still too new. But lets see how its doing just the same. As you stated it is overheating it sounds more like you have something running which is sapping your CPU’s processing causing it to run too hard given the fact you are doing light web browsing. Open Active Monitor app and sort on the % CPU what are the top 5 processes when the system is hot. You might want to get this app TG Pro its one of the better thermal monitoring apps.
