What matters

Both models share the M5 Air platform, 16GB unified memory, 512GB storage, the same display-quality baseline, Thunderbolt connectivity, fanless design, and Apple's published endurance claims. The decision is mainly how much workspace you will carry every day.

Key differences

  • The 13-inch model combines a 13.6-inch display with a 1.23kg body, while the 15-inch combines a 15.3-inch display with a 1.51kg body. The larger canvas better suits sustained split-view work; the smaller machine fits bags, laps, and travel more easily.
  • Battery capacity rises from 53.8Wh to 66.5Wh, but Apple publishes the same maximum endurance claims for both sizes. Treat the larger battery as capacity margin, not proof that the 15-inch lasts longer in a matched test.
  • Apple's official US starting prices were USD 1,099 and USD 1,299, a USD 200 gap. Because the starting GPU can differ, match GPU, 16GB memory, and 512GB storage before calling that a size-only premium.

Who it is for

  • Choose the MacBook Air 13-inch M5 if you commute, travel, work from small surfaces, or simply want the shared M5 Air baseline at the lower official starting price.
  • Choose the MacBook Air 15-inch M5 if you regularly keep documents, timelines, or tool palettes side by side and the larger canvas is worth more weight and cost.

Watch-outs

  • The hidden cost is configuration drift: the 13-inch starting GPU may be 8-core or 10-core, while the 15-inch starts with a 10-core GPU. Therefore, match GPU, 16GB memory, and 512GB storage before treating the official USD 200 starting gap as screen-only; AppleCare, tax, accessories, and promotions can also change the checkout gap.
  • The published endurance figures are vendor claims under Apple test conditions, not an independent same-method battery ranking.
  • Buy neither Air for sustained heavy CPU or GPU work that needs active cooling; that requirement points to MacBook Pro instead.