How Long to Cook Chicken Breasts at 400 Degrees
For the best results, you should bake medium-sized chicken breasts (5 to 6 ounces each) for 20 to 25 minutes in a 400-degree oven. Then, let the chicken rest for a few minutes to let the carryover heat complete the cooking process. Cooking your chicken at higher temperatures for shorter bursts of time get juicy and tender chicken on the table faster when you're pressed for time.
If you're not sure if your chicken is fully cooked, there's one simple way to know: Stick a meat thermometer into the thickest part of the biggest piece and take its temperature. If the chicken has reached 165 degrees Fahrenheit, it's safe to eat.