Sellers often search for a single percentage, but that is only part of the story. A real Etsy order can include a listing fee, a transaction fee, and a payment processing fee.
A listing that looks healthy at first glance may become weak once you include a low item price, discounted shipping, or an international payment processing rate.
Use the Etsy fee calculator on this site when you want to test several price points quickly instead of relying on one static example.