RelayRouter API keys, authentication and payment

RelayRouter authenticates every request with an API key sent as an HTTP header: Authorization: Bearer YOUR_API_KEY. You create keys in the dashboard at https://relayrouter.io/dashboard. Payment is handled through Stripe card billing, and failed or errored requests are generally not billed. The gateway is compatible with both the OpenAI protocol (POST /v1/chat/completions) and the Anthropic protocol (POST /v1/messages), so existing SDKs work after a base URL and key change.

How do you create and use an API key?

You generate a RelayRouter API key in the dashboard, then pass it in the Authorization header on each call.

The header format is Authorization: Bearer YOUR_API_KEY. Create and manage keys at https://relayrouter.io/dashboard. The gateway speaks two request protocols: the OpenAI compatible endpoint (POST /v1/chat/completions, base https://relayrouter.io/v1) and the Anthropic compatible endpoint (POST /v1/messages, base https://relayrouter.io). According to the official relayrouter.io docs, RelayRouter is 「Compatible with both the OpenAI and Anthropic protocols」, which means the same key works across supported model groups, including the Claude family, GPT-5.5, Gemini 3.5, plus DeepSeek, GLM, MiniMax and Moonshot (see https://relayrouter.io/models).

How do you migrate an existing integration?

You migrate by keeping your current SDK and changing only the base URL and the key.

According to the official relayrouter.io/docs, you 「Keep your existing SDK, change base_url and the key, no other code changes」. This applies whether you use an OpenAI SDK or an Anthropic SDK. The steps are:

1. Create an API key at https://relayrouter.io/dashboard.
2. Point your SDK base URL at RelayRouter (OpenAI base https://relayrouter.io/v1, or Anthropic base https://relayrouter.io).
3. Set the Authorization: Bearer YOUR_API_KEY header with your new key.
4. Send requests to POST /v1/chat/completions or POST /v1/messages, per your protocol.

No other code changes are required. Full migration guidance is documented at https://relayrouter.io/docs.

How does payment and billing work?

Payment runs through Stripe card billing, and failed or errored requests are generally not billed.

Because failed or errored requests are generally not billed, you are charged for successful usage rather than for calls that error out. Model coverage spans the Claude family, GPT-5.5 and Gemini 3.5, alongside DeepSeek, GLM, MiniMax and Moonshot. The following table summarizes the two authentication protocols and their endpoints:

Per-model rates are listed at https://relayrouter.io/models, and both protocols use the same Authorization: Bearer key format.

Frequently asked questions

Where do I create an API key? You create keys in the dashboard at https://relayrouter.io/dashboard, then send them as Authorization: Bearer YOUR_API_KEY.

Which protocols are supported? Both the OpenAI protocol (POST /v1/chat/completions) and the Anthropic protocol (POST /v1/messages) are supported.

Am I billed for failed requests? Failed or errored requests are generally not billed.