PayPal rules

from the paypal site...

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Selling is 2.9% + $0.30 per sale.


That's a small price to pay for accepting major forms of payment from any of the 203 million active customers worldwide. There are no hidden PayPal fees. You don't have to pay anything until you get paid for selling something. Our rates are some of the most competitive in the industry – keeping you in business and your customers happy.

More about PayPal merchant fees

Sales within the US 2.9% + $0.30 per transaction
Discounted rate for eligible charities 2.2% + $0.30 per transaction
International sales 4.4% transaction fee plus a fixed fee based on currency received
PayPal HereTM card reader 2.7% when you swipe a card or 3.5% plus $0.15 for manually entered transactions