Payment Processing Fee Calculator

Enter the transaction amount, percentage rate, and fixed fee to find the processing fee and net amount.

Result

$2.77
$82.24
3.25%

How it is calculated

The tool applies the usual two-part card fee: fee = amount × percent ÷ 100 + fixed fee. Then net = amount − fee and effective rate = fee ÷ amount × 100. The amount is what the customer pays, the percentage is the processor's rate (for example 2.9) and the fixed fee is the flat charge added to every transaction. The amount must be above zero and the percentage and fixed fee cannot be negative. Results are rounded to cents for display. The tool treats the percentage as charged on the whole amount, so it does not model separate rates for international cards, currency conversion, refunds or chargeback fees, and rates differ between processors and countries.

Worked example

A customer pays 85, the processor charges 2.9% plus 0.30. Percentage part = 85 × 0.029 = 2.465. Adding the fixed fee: 2.465 + 0.30 = 2.765, shown as $2.77. Net = 85 − 2.765 = 82.235, shown as $82.24. Effective rate = 2.765 ÷ 85 = 3.25%, higher than the headline 2.9% because the fixed fee is spread over the sale.

Try this example →

Common mistakes

  • Typing the rate as 0.029 instead of 2.9. The field expects percent, so 0.029 would mean 0.029% and nearly erase the fee.
  • Forgetting the fixed fee on small sales. On a 5 sale the same terms cost 8.90% in total, not 2.9%.
  • Entering the amount after the fee is taken. The amount must be what the customer is charged; to get a specific payout, you need to charge more.
  • Assuming one rate applies to every payment. Foreign cards, currency conversion and refunds can carry different fees which this tool does not include.

About this calculator

Payment processors typically charge merchants a blended fee made of two parts — a percentage rate (commonly around 2.9%) plus a small fixed fee per transaction (often around $0.30) — so the total fee is (amount × rate %) + fixed fee, and the net amount is the transaction total minus that fee. This structure means the effective percentage cost is actually higher on small transactions than large ones.

Ecommerce merchants and small business owners use this math to understand their true payout per sale and to compare processors like Stripe, PayPal, or Square, whose pricing follows this same percentage-plus-fixed-fee model.

Was this helpful?

You can pick up to 3 reactions.

Comments (1)

  • Editorial team

    If you want to receive a fixed amount, work backwards: price = (target net + fixed fee) divided by (1 minus the percentage as a decimal). For a net of 100 at 2.9 percent plus 0.30 that is about 103.30, and entering 103.30 here returns a net of 100.00. The effective rate then settles near 3.19 percent. What rate and fixed fee does your processor quote for the payment type you want to model?

Popular calculators

All Calculators