OpenRouter uses one key across many models. Free model IDs normally end in :free; availability and limits can change.
Get the API key
- Open OpenRouter Keys and sign in.
- Choose Create Key, enter a recognizable name, and create it.
- Copy the
sk-or-...value and store it securely.
Use the key on Free AI API
Paste the key into the API Key field on an OpenRouter endpoint page, then choose a free model and run the request.
Free variants are identified by the :free suffix. Check the endpoint page because model availability changes.
Security: never publish the key. Free AI API forwards it for the current request and does not store it on the server.