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.