To allow clients to test their API implementation, we have API functionality in our demo environment publicly available that is completely separate from the production environment and does not require existing account credentials.
To get started, just navigate to:
https://demo-futures.kraken.com/
Click the Sign up button and enter an e-mail and password combination to establish sign-in credentials to the demo environment. Please note that e-mails are disabled in this environment, therefore you do NOT need to verify the e-mail address or even have access to it. Merely note the credentials so that you may re-use them if desired. Once you have signed up, you can generate API keys for the purpose of testing. The WebSocket and REST API code on this environment is identical to the live production code in terms of the feeds/endpoints and the response structure.
To develop your implementation you can refer to the documentation here:
https://support.kraken.com/hc/en-us/sections/360012894412-Futures-API
You may also use the Github repo which has libraries coded for multiple common programming languages:
https://github.com/cryptofacilities
The only difference between the demo API behaviour and that of the live production environment is that the base URL is not futures.kraken.com but instead demo-futures.kraken.com
On the demo, for the WebSocket API you would subscribe to:
wss://demo-futures.kraken.com/ws/v1
All the feeds are identical to those documented above. So you could, e.g., subscribe to ticker feeds by sending:
{ "event":"subscribe", "feed":"ticker", "product_ids":["PI_XBTUSD","FI_ETHUSD_210625"]}
For a similar exercise on REST API you would request:
https://demo-futures.kraken.com/derivatives/api/v3/tickers
Please note that when you have successfully tested in the demo environment, the base URL in the live production platform environment works with futures.kraken.com