PCMag managed to get fifteen hours of use out of the machine in their testing. It should be noted though, that the battery life comes at the cost of raw compute performance; the Air clocks in slightly lower than other ultrabooks. However, the Air isn’t targeted at a user who is looking for a maxed out spec sheet. Since the first iteration of the Air, Apple has ruthlessly prioritised certain aspects of this laptop over others. With this latest generation, this selectivity is simply more pronounced, with an obvious sacrifice of CPU performance for battery life.