The SAP Business Accelerator Hub offers you a wide range of sandbox APIs for several SAP products like SAP S/4HANA, SAP BTP, SAP SucessFactors, SAP Concur, and more. You can use these sandbox APIs to create extensions, applications or integrations and test these with testing data provided through the sandbox API. All you need is the API key to authenticate your requests. You can get your API keys by logging in with a SAP ID account on the SAP Business Accelerator Hub and choosing Show API Key on the specific API page.
You can access the SAP Business Accelerator Hub here: https://api.sap.com/
API Reference in the SAP Business Accelerator Hub
You can browse through several sandbox APIs from several SAP products – for example, the Business Partner API from SAP S/4HANA. You can get the reference and schema for the API. You can even try out the APIs directly. The SAP Business Accelerator Hub is the place for developers and integrators to discover, explore, and consume APIs.