This is Finley from the Social Care team at Shopify. Thanks for reaching out!
The total credit card processing fee will depend on which country your business is operating from and which payment gateway you're using.
Example: The sale of a $50 dress
If you use Shopify Payments, the credit card processing fee would be (50 x 0.029) + 0.30 = $1.75 USD
If you use a third-party payment provider the fee would be 50 x 0.02 = $1 USD
Please keep in mind that third-party payment providers will charge a fee on their end for processing the transaction.
When calculating how to price your product you'll want to consider all your business costs. This will include your monthly subscription, any additional paid apps you choose to use, the cost of shipping labels, and your marketing budget.
If you're looking for more information on how to price your products, you may be interested in our article about pricing strategies that explains 13 different strategies.
If you have any further questions, please feel free to reach out.
I hope you're having a great day!