The size you need really depends on how many people you need to feed and whether you want lots of leftovers. First, decide if you want bone-in or boneless. Each will give you roughly the same amount of meat and take about the same amount of time to cook. If you want skin, go with bone-in. For this recipe, I used a Butterball turkey breast that's readily available at most grocery stores. It's a boneless 3 pound turkey breast (half breast) that will feed approximately 4-6 people with a couple of sides, or up to 8 people with small portions and lots of side dishes. You should also consider the size of your air fryer. Measure the basket and make sure that it will fit the turkey breast you want to cook.