Claude Sonnet 5.5 API pricing and integration
Claude Sonnet 5.5 through Anthropic Messages or OpenAI-compatible Chat Completions. Compare standard token rates, cache reads and both cache-write durations before connecting your application.
Use this model via API
This model is available through the paid API. Create an account, add funds and create an API key. The $2 Playground credit is for supported text models only, not API calls.
Sign up for API accessPaste the model ID, live price, base URL and a working request straight into your coding agent.
What is Claude Sonnet 5.5?
Use the exact model ID claude-sonnet-5-5. Crazyrouter exposes both /v1/messages and /v1/chat/completions for this model. The current standard schedule bills input, output, cache reads, cache writes and one-hour cache writes separately; the table below shows each rate. Sonnet 5 and Sonnet 4.6 remain separate model IDs, so test your existing prompts and tool schemas before switching.
Works with the OpenAI SDKs, LangChain, Cursor, Cline and any tool that accepts a custom base URL.
Server-sent events, function calling and JSON output behave the way the upstream model documents them.
The rates come from Crazyrouter's billing table; discounts vary by model.
Compare against Claude, GPT, Gemini, DeepSeek and more without juggling vendor accounts.
Claude Sonnet 5.5 API quickstart
Point your OpenAI SDK at https://api.crazyrouter.com/v1 and set the model to claude-sonnet-5-5. If your client speaks Anthropic Messages natively, use the second example instead.
curl https://api.crazyrouter.com/v1/chat/completions \
-H "Content-Type: application/json" \
-H "Authorization: Bearer $CRAZYROUTER_API_KEY" \
-d '{
"model": "claude-sonnet-5-5",
"messages": [{"role": "user", "content": "Explain the tradeoffs of this architecture decision."}],
"stream": true
}'Show OpenAI-compatible migration example
curl https://api.crazyrouter.com/v1/messages \
-H "Content-Type: application/json" \
-H "x-api-key: $CRAZYROUTER_API_KEY" \
-H "anthropic-version: 2023-06-01" \
-d '{
"model": "claude-sonnet-5-5",
"max_tokens": 2048,
"messages": [{"role": "user", "content": "Explain the tradeoffs of this architecture decision."}],
"stream": true
}'Where to buy claude-sonnet-5-5: price by provider
Published provider prices per 1M tokens, input (dark) / output (light). Provider listings do not identify Crazyrouter upstream routes.
What that means in practice
Best use cases
Works with developer tools
OpenAI SDKs
Set base_url to https://api.crazyrouter.com/v1 and model to claude-sonnet-5-5.
Cursor, Cline, Continue
Add Crazyrouter as a custom OpenAI-compatible provider and pick the model from the list.
LangChain / LlamaIndex
Use the OpenAI chat model class with the Crazyrouter base URL.
Claude Code / Codex CLI
Follow the Crazyrouter deployment guides to point either CLI at your key.
Claude Sonnet 5.5 FAQ
What base URL do I use for Claude Sonnet 5.5?
https://api.crazyrouter.com/v1. Chat completions go to /v1/chat/completions; native Anthropic Messages requests use their usual path.
How is usage billed?
Per token, at the input/output rates shown on this page. Your balance is debited per request; there is no subscription.
Does it support streaming and function calling?
Yes. Set stream: true and pass tools as you would with the upstream API. Behaviour follows the upstream model.
Can I switch to another model later?
Change the model string. The same key works for every model in the Crazyrouter catalogue.
Where do I see the current price?
The pricing page lists live rates for every model, including group discounts if you are logged in.