Commerce APIs let you add commerce capabilities without building from scratch. Every entry below is profiled with trust signals — pricing model, authentication requirements, CORS support, rate limits, and live uptime checks — so you can compare options and pick production-safe choices instead of guessing from a link list.
| API | Pricing | Auth | CORS | Health | |
|---|---|---|---|---|---|
| BigCommerce API BigCommerce API: headless commerce platform for catalog management, orders, customers, storefronts, and checkout. | Freemium | API Key | No | Profile | |
| Lemon Squeezy API Merchant of record API for products, variants, orders, subscriptions, licenses, and webhooks. | Freemium | API Key | Yes | Profile | |
| Polar API Open-source payments and monetization API for products, checkouts, subscriptions, and benefits. | Freemium | API Key | Yes | Profile | |
| Shopify GraphQL Admin API GraphQL Admin API for Shopify products, orders, customers, inventory, and store operations. | Freemium | API Key | Yes | Profile |
Start with pricing and auth: free tiers and no-auth APIs are fastest to prototype with. Then check CORS if your app calls the API from the browser, and health before you commit — a great API that's been down for a week will block your launch. Each profile below shows all of these signals plus rate limits where documented.