Measuring MacBook battery life in straight hours of real-world usage (as Apple likes to do) is not always an accurate metric for comparison purposes as so many use and environmental factors play a part. We can, however, rely on straight technical specifications to tell us the stated battery capacities of each MacBook.
Where Apple is secretive about iPhone battery specifications (see our list of iPhone battery capacities based on teardowns), the company does list MacBook capacities in Watt hours (Wh). We have trawled through the Apple product Tech Specs pages from 2009 to 2024 to bring you as complete a list as we can gather using official Apple battery declarations.
The watt-hour is a unit of energy equivalent to one watt (1W) of power utilized for one hour of time. it is calculated by multiplying the number of Amps with the battery voltage. The higher the number of Wh the longer a battery will last using the same application. Batteries will lose efficiency over time so don’t expect a 2009-era MacBook battery to still possess the same power as it did when it was new or more than a 2024 model, even if it had an originally higher Wh rating.
Read more at Macworld.com