Sources & References
This page lists the primary public references used across the site. These sources are useful for validation, deeper reading, and confirming provider-specific behavior.
Payment testing sources
Stripe testing docs: https://docs.stripe.com/testing?testing-method=card-numbers
Adyen test card numbers: https://docs.adyen.com/development-resources/testing/test-card-numbers/
Checkout.com test cards: https://www.checkout.com/docs/developer-resources/testing/test-cards
Airwallex test card numbers: https://www.airwallex.com/docs/payments__test-card-numbers
Fee comparison sources
Stripe pricing: https://stripe.com/pricing
Adyen pricing: https://www.adyen.com/pricing
Checkout.com pricing: https://www.checkout.com/pricing
Airwallex pricing: https://www.airwallex.com/pricing
Reference note
Public documentation and pricing pages can change. When in doubt, provider-owned docs should be treated as the source of truth for final implementation behavior or commercial terms.
Quick answers
Which sources are preferred?
Provider-owned documentation and public pricing pages are preferred because they are the most authoritative source for sandbox behavior and published pricing assumptions.
What should users do if provider behavior changes?
Users should validate final implementation behavior against the provider-owned docs and report stale site references through the contact page.