First, click the Apple logo in the upper left-hand corner.
Click "System Preferences."
In the left-hand column, select "Battery."
Here you can see your battery health, which should ideally say "Normal."
You can also see the maximum capacity of your battery, which tells you if your battery can charge to the full 100% capacity. Naturally, batteries degrade overtime, so as long as your battery is above 75%, you should not consider replacing your battery unless it has exceeded the maximum cycle count.
However, here, instead of "Normal," it may say that your Mac needs service. If it does, this means that you simply need to look into servicing your battery at Apple or an Authorized Service Provider.
Because your MacBook is so important for all that you do in a day, it is important to take good care of your Mac battery, monitor your Mac's battery health, and check the cycle count of your Mac's battery when to determine if your Mac needs a new battery. This might sound like a lot of maintenance, but checking your Mac's cycle count is an easy way to determine if your Mac needs a new battery, and it's actually incredibly simple. A battery's maximum cycle count is how many charge cycles your Mac can complete before the battery is no longer able to perform and will need replacing. In this guide, I show you how to check your Mac battery's cycle count and determine if your battery needs to be replaced.