Payment Processing Fees Calculator
Instantly calculate how much a payment gateway like Stripe or PayPal will charge per transaction. Enter your transaction amount, percentage fee, and fixed fee to see your net revenue.
About this calculator
Payment processors typically charge a blended fee: a percentage of the transaction plus a small fixed amount. The formula is: Processing Fee = (transactionAmount × feePercent / 100) + fixedFee. For example, Stripe charges 2.9% + $0.30 per transaction. As transaction amounts grow, the percentage component dominates, but for small purchases the fixed fee can represent a surprisingly large share of the total cost. Merchants use this calculation to set minimum order thresholds, decide which processor to use, and correctly price products so margins are preserved after fees are deducted. Understanding your effective fee rate — total fee divided by transaction amount — helps benchmark processors against each other.
How to use
Suppose you sell a product for $50.00 and your processor charges 2.9% + $0.30. Enter Transaction Amount = $50, Fee Percentage = 2.9, Fixed Fee = $0.30. The calculator computes: Fee = (50 × 2.9 / 100) + 0.30 = $1.45 + $0.30 = $1.75. Your net revenue after fees is $50.00 − $1.75 = $48.25. If you raise the transaction to $200, the fee becomes (200 × 0.029) + 0.30 = $5.80 + $0.30 = $6.10, showing how the percentage component scales with order size.
Frequently asked questions
How do payment processing fees affect my profit margin on small transactions?
On small transactions, the fixed fee component becomes proportionally very large. A $0.30 fixed fee on a $3.00 sale represents 10% of the transaction before the percentage fee is even added. This is why many merchants set minimum purchase amounts or add surcharges for low-value orders. Calculating the effective fee rate (total fee ÷ transaction amount) for each price point helps you identify where your margins are squeezed most.
What is the difference between a flat-rate and interchange-plus payment processing fee structure?
Flat-rate pricing (like Stripe's 2.9% + $0.30) charges the same percentage regardless of card type, making costs predictable and easy to calculate. Interchange-plus pricing passes the actual card network interchange rate through to the merchant and adds a fixed markup, which can be cheaper for high-volume businesses but harder to forecast. This calculator models flat-rate or blended-rate structures where a single percentage and fixed fee apply per transaction.
How can I price my products to fully cover payment processing fees?
To recover a fee of the form (amount × p) + f, you can solve for the gross price needed: grossPrice = (netPrice + f) / (1 − p). For a desired net of $48.25 with 2.9% + $0.30, you'd charge (48.25 + 0.30) / (1 − 0.029) ≈ $50.00. This fee-inclusive pricing strategy ensures the customer effectively absorbs the processing cost, which is common in e-commerce and service businesses.