Methodology & data sources

Transparency is the core of our E-E-A-T. This page documents exactly where each payment-processing fee comes from, when it was captured, and the formulas behind every derived figure. We track 20 processors across 8 payment methods.

Snapshot date & volatility

All fees on this site are a dated snapshot (June 2026). Payment-processing pricing changes without notice and varies by region, card type, volume, risk profile and the contract you sign. Verify on the provider's pricing page before relying on a figure. We do not fabricate numbers: where a processor does not publish a single blended rate, we render the pricing model (interchange-plus, subscription, Merchant-of-Record) rather than invent one.

Pricing models — and why some have no single rate

• Flat rate (Stripe, Square, PayPal, Braintree, Amazon Pay): one blended percentage + fixed fee, e.g. 2.9% + $0.30. We can compute an exact effective rate for any ticket size.
• Interchange-plus (Adyen, Checkout.com, Helcim, Worldpay): interchange (set by card networks) + scheme fees + a small processor markup. The effective rate depends entirely on your card mix, so we show the markup/structure, not a fake flat total. For Helcim we show an illustrative effective rate built from a typical consumer-card interchange plus the published margin, clearly labeled as illustrative.
• Subscription / membership (Stax): a flat monthly fee + interchange at cost (0% markup) + a small fixed per-transaction fee. There is no percentage markup to blend without your volume.
• Merchant of Record (Paddle, Lemon Squeezy, 2Checkout): a higher all-in rate that bundles global sales-tax/VAT remittance, fraud and chargeback handling. We show the published rate and note what it includes.
• Per-method (Mollie, GoCardless): priced per payment method (cards vs iDEAL vs SEPA), not one card rate.

Per-processor pricing models & sources

How we derive figures

• Effective rate for a ticket of size T = pct% + (fixed fee / T) x 100. The fixed fee weighs more on small tickets, which is why a 2.9% + $0.30 processor is ~5.9% effective on a $10 sale but ~3.05% on a $200 sale. Our headline effective figures use a $50.00 reference ticket.
• Calculator total = volume x pct% + fixed fee x transactions + cross-border surcharge on the international share + any fixed monthly fee. The effective rate = total / volume x 100. It runs entirely in your browser; we don't store inputs.
• Rankings sort processors by their published effective rate (cheapest-for-small-business), pricing-model suitability (high-volume), international surcharge, or chargeback fee. Ties break alphabetically.

Data sources (summary)

What's excluded

Our headline rates and the calculator focus on the core processing fee. They do not include chargeback/dispute fees (shown separately on each processor page), currency conversion beyond the cross-border surcharge, PCI compliance and statement fees, hardware costs, refunds, or negotiated/volume discounts — all of which can change your real bill.

Limitations & accuracy

Figures are estimates for general information and may lag the underlying source or contain errors. This is an informational comparison, not a quote, offer, or financial advice. Always verify against the provider's primary pricing page and read the contract before signing. See our disclaimer.

Last updated: 2026-06-29