Increase API

Sign in to the Increase Dashboard, open Developers → API Keys, and create or copy an API key. Increase provides separate keys for production and sandbox; use the production key with https://api.increase.com and the sandbox key with https://sandbox.increase.com. Send it as Authorization: Bearer <key>.

To build an app for other Increase users, sign in to the Increase Dashboard and create an OAuth app at Developers → OAuth applications. Set a name and redirect_url; Increase gives you a client_id and client_secret. Direct users to https://increase.com/oauth/authorization?client_id={client_id}&state={state}&scope={scope} with scope set to read_only or read_write, then exchange the returned code by POSTing to https://api.increase.com/oauth/tokens with your client_id, client_secret, the code, and grant_type authorization_code. Store the returned access token for API calls on behalf of that user.