When you're looking to buy a laptop, battery life is going to affect your decision significantly. You have to think about what type of use you are dealing with and how often you will be using the laptop to determine which battery is going to be best. Apple laptops are certainly not designed with the best battery life, by any means, but they can provide sufficient performance for many people and that makes up for it. The actual results vary depending on how the laptop is used and what type of specifications it has, but there are some general rules to help you determine which laptops will get the best battery life.
Apple laptops are designed for performance. With that being said, the best laptop for battery life seems to be the MacBook in the 12" or 13" version. While there are many variables involved, the smaller screen and lower specifications seem to take up less battery life. These laptops have been known to get 4-5 hours of life depending on their use. Of course, if you have a larger screen and are doing fewer things or simply browsing the internet, for example, you might still get good battery life out of your Apple laptop.
In Apple history, the G3 Prismo that had the dual-battery option had the longest battery life, providing 5-6 hours of regular use in most every situation. Today's laptops from Apple are feature-rich and designed to get things done, however, so battery life is not an optimal feature like it is in some PCs that you find on the market today. Models like the Toshiba Satellite series can easily get up to 8 hours of battery life depending on use, and you will never find an Apple that comes close to that with a single charge.
All told, the smaller screen and more basic specifications are going to be best for an Apple laptop to hold a charge. Of course, the use of the laptop will affect the battery life, as well. Two people could have the exact same computer and get completely different results from their battery life simply because they use the computers differently. Take the time to think about your usage, the type of laptop you prefer, and the specifications of the laptop to help you get a better idea of how long your Apple laptop will last before you make a purchase.