The amount of charge capacity your MacBook should run down to before the battery should be replaced is up to you. For example, if your MacBook can hold a 50% charge, it means that it can only hold half of the charge that it could have when it was new. If your MacBook is a few years old (or more), the battery may have worn out and be unable to hold much charge. To test exactly how worn out your MacBook's battery is, you can download a free application called Coconut Battery that will tell you what percentage of charge the battery can hold. If your battery is lasting significantly shorter than this, you may have a problem and are advised to read the rest of this article. Realistically, one might get 3-5 hours browsing the web, 2-3 hours watching MP4 videos, and even only 1-2 hours consuming Flash Content on a healthy battery. Apple claims 7 hours of battery life for the MacBook Pros and MacBook Airs, however, the battery tests that were used to make this claim were performed under stringent conditions, conditions which you cannot expect to emulate under everyday usage.
When looking at ways to improve your MacBook's battery life, the first thing you must do is determine whether it is substandard, as there is no point in trying to improve your MacBook's battery life if it's already reaching its full potential.
