To test integration, you will need the demo store in Yandex.Checkout. The payment process in the demo store is identical to the actual payment process, except the money is not transferred anywhere.
To access the demo store, sign up for Yandex.Checkout:
  • during the registration process, specify your company’s Taxpayer Identification Number (INN);
  • select the API (for self-made websites) integration method in the settings.
You don’t need to enter into a contract and complete the full registration cycle.
Get the OAuth token for the demo store and use it to make test payments.
See also
OAuth authorizationNotificationsPayment processPayment by 54-FZTesting payments