# Stripe billing ## The Stripe schema To help understand subscriptions, it's useful to know how Stripe structures its data.

As we can see, a Subscription comprises several SubscriptionItems, which each match to a Price. This allows you a large amount of flexibility in constructing your subscription plans. Think of a plan in terms of a collection of Prices. Thus, when you want to define plans for your users to buy, you: * Create a Product in Stripe * For that product, you create any number of prices - usually a monthly and yearly price * You copy the Price IDs and add them to your Petal Pro config as `items`:

Usually, you will only have one "item" in there. But sometimes you may want to add two - eg. you might have a once-off price as well as a monthly price. Quantity will also mostly stay the same - 1. If your plans have a number of seats - then `quantitiy` would represent that variable. The other info in the config is mainly for your front-end UI. The Stripe Prices are the main thing you want to copy across from Stripe. ### How our config is used to create checkout sessions * Explain what a checkout session is, how our items are passed in as line items and how it generates a hosted checkout page Stripe * Explain how webhooks work and how we use Oban These docs are a work in progress. Expect more soon! For now follow the ["Adding a subscription" guide](https://docs.petal.build/petal-pro-documentation/v2.2.0/guides/adding-a-subscription).