How long do chicken breasts need to stay in the oven at 450?

Thanks!

You can also check by pushing with your fingertips but for food safety's sake I wouldn't use this method for chicken unless you're confident. Without a meat thermometer I would cut to check for doneness. Also the juices should run clear. For thinner breasts 15 min at 450 should be ample. Don't want to over cook them or they'll dry out.

Yes boneless they are pretty wide but not overly thick...any way to check if they are done without cutting into them? I don't have a thermometer tho

Boneless? Depends on how big they are... About 15-20 minutes or until they've reached an internal temp of 165.