This page explains which official provider pages to verify before relying on a SaaS payment-fee estimate. The calculator is useful for planning, but provider pricing can vary by country, plan, currency, payment method, and negotiated agreement.
| Provider | Official source | What to verify |
|---|---|---|
| Stripe | Stripe pricing | Card rate for your country, international-card fees, dispute fees, currency conversion, Stripe Tax, Billing, invoicing, and any custom pricing. |
| Paddle | Paddle pricing | Pay-as-you-go checkout rate, low-ticket rules, custom pricing, migration needs, invoicing, and merchant-of-record coverage. |
| Lemon Squeezy | Lemon Squeezy pricing | Transaction fee, extra payment-method fees, email-plan pricing, volume pricing, and what is included in merchant-of-record support. |
| Polar | Polar pricing | Selected plan, payment fees, merchant-of-record fees, dispute fees, additional fees, and whether open-source or startup pricing applies. |
Last reviewed for link availability: June 17, 2026. Always verify the live provider page before making a checkout decision.
A checkout decision is usually made before a founder has perfect finance data. The calculator therefore focuses on the inputs that most often change the answer: revenue, order count, average order value, international card share, refunds, and chargebacks.
This keeps the model readable. A founder can run a few scenarios quickly, then verify the final edge cases on the provider's official pricing page.
Providers may price differently by country, currency, payment method, transaction type, volume, plan, or sales-negotiated agreement. A public fee estimate can also exclude optional products such as tax automation, subscription management, invoicing, instant payouts, or premium support.
If your business is near break-even between two providers, verify every add-on that could apply before switching checkout infrastructure.
Stripe is usually modeled as direct payment processing. Before using the estimate, verify the card pricing for your account country, international cards, currency conversion, dispute fees, Stripe Billing, Stripe Tax, invoice fees, and any custom agreement.
For Paddle, Lemon Squeezy, and Polar, verify what the merchant-of-record fee includes. Tax handling, invoices, buyer support, refunds, fraud workflows, and chargeback handling are operational differences, not just fee-line differences.
Update assumptions when pricing changes, your customer geography changes, average order value drops, refund or chargeback rates move, or you switch from monthly to annual billing. A provider that wins for a domestic $99 plan may not win for a global $9 plan.
Run the calculator first to find the sensitive variables. Then open the official provider page and verify only the fee lines that matter to the scenario. This is faster than reading every pricing page from scratch.
No. They are estimates for planning. Use official provider pricing pages and your own account terms before making a final decision.
Provider pages can be localized, plan-specific, or account-specific. A transparent source checklist is safer than pretending every checkout edge case can be updated automatically.
Yes. Direct processing plus a tax product can be a very different operational setup from a merchant-of-record provider. Compare both the fee and the work your team keeps.