# Documentation - PayNext

## Docs

- [Create a client session](https://docs.paynext.com/api-reference/client-session/create-a-client-session.md): Create a client session
- [Update a client-session](https://docs.paynext.com/api-reference/client-session/update-a-client-session.md): Update a client-session
- [Create a customer](https://docs.paynext.com/api-reference/customers/create-a-customer.md): Create a customer
- [Find a customer](https://docs.paynext.com/api-reference/customers/find-a-customer.md): Find a customer by id
- [Find customers](https://docs.paynext.com/api-reference/customers/find-customers.md): Find customers
- [Update a customer](https://docs.paynext.com/api-reference/customers/update-a-customer.md): Update a customer by id
- [Authentication](https://docs.paynext.com/api-reference/introduction/authentication.md): Authenticate PayNext Billing API requests using API keys in the Authorization header.
- [Errors](https://docs.paynext.com/api-reference/introduction/error-codes.md): Understand PayNext Billing API error codes and response formats.
- [Getting Started](https://docs.paynext.com/api-reference/introduction/getting-started.md): Get up and running with the PayNext Billing API for payment processing, subscription management, and customer billing operations.
- [Create a payment](https://docs.paynext.com/api-reference/payments/create-a-payment.md): Create a payment
- [Find a payment by id](https://docs.paynext.com/api-reference/payments/find-a-payment-by-id.md): Find a payment by id
- [Find payments](https://docs.paynext.com/api-reference/payments/find-payments.md): Find payments
- [Refund a payment](https://docs.paynext.com/api-reference/payments/refund-a-payment.md): Refund a payment
- [Find a plan](https://docs.paynext.com/api-reference/plans/find-a-plan.md): Find a plan by id
- [Find plans](https://docs.paynext.com/api-reference/plans/find-plans.md): Find plans
- [Cancel a subscription](https://docs.paynext.com/api-reference/subscriptions/cancel-a-subscription.md): Cancel a subscription
- [Create a subscription](https://docs.paynext.com/api-reference/subscriptions/create-a-subscription.md): Create a subscription
- [Find a subscription](https://docs.paynext.com/api-reference/subscriptions/find-a-subscription.md): Find a subscription
- [Find subscriptions](https://docs.paynext.com/api-reference/subscriptions/find-subscriptions.md): Find subscriptions
- [Schedule cancellation of a subscription](https://docs.paynext.com/api-reference/subscriptions/schedule-cancellation-of-a-subscription.md): Schedule cancellation of a subscription
- [Update a subscription](https://docs.paynext.com/api-reference/subscriptions/update-a-subscription.md): Update a subscription
- [Device Fingerprinting](https://docs.paynext.com/guides/advanced/device-fingerprinting.md): Automatically capture browser, device, and location data for fraud prevention and dispute protection.
- [Metadata Mapping](https://docs.paynext.com/guides/advanced/metadata-mapping.md): Forward custom data to processors during payment authorization.
- [API Keys](https://docs.paynext.com/guides/developers/api-keys.md): Create and manage scoped API keys with permission-based access control.
- [MCP Server](https://docs.paynext.com/guides/developers/mcp-server.md): Connect PayNext documentation to AI tools like Claude, Cursor, and VS Code using the Model Context Protocol.
- [Core Concepts](https://docs.paynext.com/guides/introduction/core-concepts.md): Understand how PayNext works: smart routing, workflows, and unified control across processors.
- [Testing & Sandbox](https://docs.paynext.com/guides/introduction/testing-and-sandbox.md): Test your integration in sandbox before going live with production payments.
- [3D Secure](https://docs.paynext.com/guides/payments/3d-secure.md): Configure 3DS authentication for card payments.
- [Currencies](https://docs.paynext.com/guides/payments/currencies.md): Currency reference for PayNext.
- [Decline Codes](https://docs.paynext.com/guides/payments/decline-codes.md): Unified status mapping across all processors—understand why a payment failed and whether to retry.
- [Lifecycle](https://docs.paynext.com/guides/payments/lifecycle.md): Understand how payments move through statuses from creation to completion.
- [Checkout](https://docs.paynext.com/guides/platform/checkout.md): Configure which payment methods appear in checkout and set conditional display rules.
- [Plans](https://docs.paynext.com/guides/platform/plans.md): Create and manage billing plans—define pricing, billing intervals, trial periods, and localized currencies.
- [Roles & Permissions](https://docs.paynext.com/guides/platform/roles-and-permissions.md): Control what teammates can access and manage in your PayNext organization.
- [Subscriptions](https://docs.paynext.com/guides/platform/subscriptions.md): Manage recurring billing—create subscriptions, handle trials, process renewals, and recover failed payments.
- [Taxes](https://docs.paynext.com/guides/platform/tax.md): Automatically calculate and collect sales tax on payments and subscriptions.
- [Workflows](https://docs.paynext.com/guides/platform/workflows.md): Route payments intelligently with no-code rules. Optimize costs, increase acceptance rates, and implement failover logic.
- [Accept a Payment](https://docs.paynext.com/guides/use-cases/accept-a-payment.md): Accept your first payment from a new customer using the PayNext SDK.
- [Change Subscription Plan](https://docs.paynext.com/guides/use-cases/change-subscription-plan.md): Upgrade or downgrade a customer's subscription—charge immediately or schedule for next billing cycle.
- [Charge Returning Customers](https://docs.paynext.com/guides/use-cases/charge-returning-customers.md): Charge customers who already have a payment method on file—SDK checkout or API-only.
- [Display Local Pricing](https://docs.paynext.com/guides/use-cases/display-local-pricing.md): Display both local and payment currencies at checkout with pre-formatted amounts from the API.
- [Recover Subscriptions](https://docs.paynext.com/guides/use-cases/recover-subscriptions.md): Collect payment for failed subscription renewals and reactivate past-due or cancelled subscriptions.
- [Introduction](https://docs.paynext.com/index.md): PayNext is a modern payments platform. Route payments across processors, manage subscriptions, and build checkout experiences—all from a single integration.
- [Overview](https://docs.paynext.com/integrations/overview.md): Connect processors and payment methods through a unified payment layer.
- [Amazon Pay](https://docs.paynext.com/integrations/payment-methods/amazon-pay.md): Accept Amazon Pay payments through PayNext.
- [Apple Pay](https://docs.paynext.com/integrations/payment-methods/apple-pay.md): Accept Apple Pay payments through PayNext.
- [Cards](https://docs.paynext.com/integrations/payment-methods/cards.md): Accept card payments through PayNext.
- [Cash App](https://docs.paynext.com/integrations/payment-methods/cashapp.md): Accept Cash App payments through PayNext.
- [Google Pay™](https://docs.paynext.com/integrations/payment-methods/google-pay.md): Accept Google Pay™ payments through PayNext.
- [PayPal Wallet](https://docs.paynext.com/integrations/payment-methods/paypal-wallet.md): Accept PayPal payments through PayNext.
- [Pix](https://docs.paynext.com/integrations/payment-methods/pix-automatico.md): Accept Pix payments through PayNext.
- [Venmo](https://docs.paynext.com/integrations/payment-methods/venmo.md): Accept Venmo payments through PayNext.
- [Braintree](https://docs.paynext.com/integrations/processors/braintree.md): Accept payments via Braintree with PayNext.
- [Nuvei](https://docs.paynext.com/integrations/processors/nuvei.md): Accept card payments via Nuvei with PayNext.
- [PayPal](https://docs.paynext.com/integrations/processors/paypal.md): Accept payments via PayPal with PayNext.
- [Stripe](https://docs.paynext.com/integrations/processors/stripe.md): Accept payments via Stripe with PayNext.
- [Unlimit](https://docs.paynext.com/integrations/processors/unlimit.md): Accept payments via Unlimit with PayNext.
- [Worldpay](https://docs.paynext.com/integrations/processors/worldpay.md): Accept card payments via Worldpay with PayNext.
- [Numeral](https://docs.paynext.com/integrations/tax-providers/numeral.md): Automate US sales tax calculation and compliance with Numeral.
- [Data Processing Agreement](https://docs.paynext.com/legal/dpa.md): Agreement governing how PayNext processes personal data on your behalf.
- [Privacy Policy](https://docs.paynext.com/legal/privacy.md): How PayNext collects, uses, and protects your personal information.
- [Terms of Service](https://docs.paynext.com/legal/terms.md): Terms and conditions governing use of the PayNext platform and services.
- [Quickstart](https://docs.paynext.com/sdk-reference/introduction/getting-started.md): Integrate PayNext SDK to accept payments with minimal code.
- [Charge Saved Payment Methods](https://docs.paynext.com/sdk-reference/use-cases/charge-saved-payment-methods.md): Client session payloads for one-time charges, plan changes, and recovery flows.
- [Handle Expired Sessions](https://docs.paynext.com/sdk-reference/use-cases/handle-expired-sessions.md): Manage client session expiration and create new sessions when needed.
- [Card Networks](https://docs.paynext.com/sdk-reference/web-sdk/constants/card-networks.md): Configure the card networks to accept in the PayNext SDK checkout form.
- [Environments](https://docs.paynext.com/sdk-reference/web-sdk/constants/environment-types.md): Configure the environment to use for the PayNext SDK checkout form.
- [Locales](https://docs.paynext.com/sdk-reference/web-sdk/constants/locale-types.md): Supported languages for PayNext checkout form. Automatic translation with optional manual override.
- [Payment Methods](https://docs.paynext.com/sdk-reference/web-sdk/constants/payment-method-types.md): Available payment methods supported by PayNext. Configure them directly in your Dashboard.
- [Integration Patterns](https://docs.paynext.com/sdk-reference/web-sdk/customization/advanced-usage.md): Practical patterns that combine functional and visual customization of the PayNext SDK.
- [Customize the Appearance](https://docs.paynext.com/sdk-reference/web-sdk/customization/appearance.md): Style the PayNext SDK checkout form to match your brand using CSS-in-JS, CSS classes, and wallet-specific theming.
- [Customize Checkout Behavior](https://docs.paynext.com/sdk-reference/web-sdk/customization/behavior.md): Configure payment methods, validation rules, and callbacks to optimize checkout form completion rates.
- [Customize Text & Translations](https://docs.paynext.com/sdk-reference/web-sdk/customization/text-and-translations.md): Customize checkout form text content to match your brand voice and support multiple languages including right-to-left layouts.
- [Theme Support](https://docs.paynext.com/sdk-reference/web-sdk/customization/theme.md): Configure light, dark, or system-driven themes for the PayNext Checkout.
- [Overview](https://docs.paynext.com/sdk-reference/web-sdk/index.md): Customize the PayNext SDK appearance and behavior to match your brand and optimize your checkout flow.
- [Event Types](https://docs.paynext.com/webhooks/introduction/event-types.md): Learn about PayNext webhook event types for payments and subscriptions, including when they fire and how to use them in your application.
- [Getting Started](https://docs.paynext.com/webhooks/introduction/getting-started.md): Set up webhooks to receive real-time notifications about payments, subscriptions, and customer events.
- [Transformations](https://docs.paynext.com/webhooks/introduction/transformations.md): Modify webhook properties in-flight using JavaScript code.
- [Payment](https://docs.paynext.com/webhooks/objects/payment/payment.md)
- [Subscription](https://docs.paynext.com/webhooks/objects/subscription/subscription.md)

## OpenAPI Specs

- [openapi3](https://docs.paynext.com/api-reference/openapi3.json)
- [swagger](https://docs.paynext.com/src/api-reference/swagger.yaml)