Payment Processor Fee Calculators

How Payment Processing Fees Work

Payment processors charge a percentage of each transaction plus a fixed fee. Unlike marketplace fees, there are no listing fees, commission percentages, or platform cuts — just the cost of moving money from your customer's card to your bank account.

Traditional processors like PayPal, Stripe, and Square have converged on similar online rates (roughly 2.9% + $0.30), while newer options like Venmo Business (1.9% + $0.10) and interchange-plus providers like Helcim and Adyen can be significantly cheaper. Buy Now, Pay Later services like Afterpay and Klarna charge merchants 4–6% but can boost conversion rates. Our calculators show you the exact fee on any transaction amount so you can price your products accordingly.

For most businesses, the choice between processors comes down to use case rather than fees: Square for in-person + online, Stripe for developer-heavy integrations, and PayPal for trusted checkout conversion.