Is there an accessible up-to-date fee calculator for eBay PayPal etc.

iOS and iPadOS

Hello, as my subject line clearly states I am searching for an accessible eBay and PayPal fee calculator. I have found one that is accessible but has not been updated in over two years. I checked on this site and could not find an app listed that is anything close to what I'm looking for. When I looked at the App Store they had several for between $.99 and about five dollars. There were also a few free ones listed but their ratings and the details and descriptions led me to believe that they wouldn't be very good. Most of them have not really been updated in quite a while. I would not mind paying about five dollars for an application I just don't want to have to spend the money and find out it doesn't work not to mention a hassle to get my money refunded. If there is no program available maybe someone has a formula written for numbers? I was hoping to just sort of be able to plug it in I'm just not very good with spreadsheets. Thanks so much for any help that y'all can provide.