API overview - Ionic Docs

Fundamentals

Payments

Checkout

In-person payments

Customers and catalog

Connect

Billing

Webhooks

Use the guides to build a complete integration. Use this reference for endpoint paths, permissions, request fields, responses, and errors.

Endpoints by product

Product	Resources	Start with
Payments	Payment intents, charges, refunds, setup intents, payment methods, web domains	Ways to accept payments, Save a card for later
Checkout	Checkout sessions, payment links	Hosted Checkout
In-person payments	Terminal payments, terminals, terminal provisioning, terminal batches, terminal locations, terminal testing	In-person terminal payments
Customers and catalog	Customers, products and prices	Manage customers, Catalog
Connect	Account links, account authorizations, connected accounts	How Connect works
Billing	Subscriptions, invoices, credit notes, test clocks	Subscriptions, Invoices, Credit notes
Webhooks	Webhook endpoints	Webhooks quickstart

Ionic Blocks uses payment intents, setup intents, and payment methods. A platform acts for a connected account with Ionic-Account on endpoints that list it; see Platforms and connected accounts.

Shared behavior

Topic	Why it matters
Authentication	Server-side requests use secret keys. Hosted checkout URLs stay buyer-facing.
Request and response shape	Common resource shape, timestamps, nullability, and metadata.
IDs	Prefixes such as `cs_`, `pl_`, `prod_`, `price_`, `cus_`, and `rf_`.
Idempotency	Safe retries for create and refund requests.
Errors	Standard error envelope and payment decline details.
Pagination	List endpoint pagination patterns.
Rate limits	Headers and retry behavior.
Backwards compatibility	How the API evolves without breaking integrations.