You can see if the MacBook is still under warranty or protected under AppleCare. One is having Apple take care of it with service ranging from $130 to $200. If it's indeed time for a replacement, you’re afforded three options. From there, select Power and check the battery’s current cycle run. Hold down the Alt key and click the Apple icon at the top left, and choose System Report/Profiler. Common sense suggests replacing the cell if prompted, but you can dig deeper into the issue by checking the cycle count on the back end. You can check the condition of your battery by clicking the battery icon on the top right, where you’ll see one of four conditions: Normal, Replace, Replace Now, or Service Battery. Apple also claims 'your battery is designed to retain up to 80 percent of its original capacity at 1,000 complete charge cycles.' That’s not 100 percent. Each cycle is measured when the machine uses all the battery’s power and then fully recharges it.

Want to know why your MacBook can’t hold a charge the way it used to? Most modern models have a limited charge cycle of 1,000.

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