Anthropic
Claude Opus 5
From $2.40 per 1M tokens
Chat
Claude Sonnet 4.6 API — Anthropic's Balanced Everyday Model
Claude Sonnet 4.6 is Anthropic's balanced everyday model — Claude-grade output quality at fast latency. 1M context, 128K max output, vision input, and standard /v1/chat/completions for high-volume production traffic that doesn't need Opus-tier reasoning on every call.
- Highlights
- Speed / quality balance · streaming chat
- Best for
- Chat products, summarization, drafting
- Input
- Chat messages (OpenAI-compatible)
- Output
- Text, streaming optional
Claude Sonnet 4.6model
claude-sonnet-4-6Claude Sonnet 4.6 playground
Chat models run on the api.reapi.ai gateway, which has its own console and its own key. Open the console to run Claude Sonnet 4.6 through the OpenAI-compatible Chat Completions surface.
What is the Claude Sonnet 4.6 API?
Claude Sonnet 4.6 is Anthropic's balanced everyday model, built for production traffic that needs Claude-grade output at fast latency — support chat, code review, mid-complexity agents, summarisation. It keeps the family's 1M-token context window and 128K max output per call, adds vision input, tool use, and the temperature and top_p controls, and answers on an OpenAI-compatible /v1/chat/completions endpoint (the native /v1/messages surface is available too). Usage is billed per million tokens, with input and output priced separately.
What you can build with this model
Real-world workflows and production use cases you can build and ship with this model.
High-volume production chat and support
Run Claude Sonnet 4.6 as the default model behind a chatbot, support assistant, internal copilot, or onboarding flow. Claude-grade reasoning at production-friendly latency — fast enough for live UX, smart enough that the answers hold up under user scrutiny.
Read the API docs
Code review, refactor suggestions, and PR triage
Plug Claude Sonnet 4.6 into your code-review pipeline. It reads diffs in context, flags real bugs, suggests cleaner naming, and writes follow-up commits — fast enough for inline-suggestion UX and rigorous enough that the comments are worth reading.
Mid-complexity agent workflows
Build agents that need solid tool use and reasonable planning without the Opus-tier price-per-call. Sonnet handles multi-step tool calling, structured outputs, and recovery from tool errors — the right default for production agents that run at scale.
Pricing
Credit-based — 1 credit = $0.001 USD. Pay only for completed generations.
First test cost
$2.42,400 credits
One sample at the cheapest tier (1M tokens).
Testing budget guide
Add credits$10
≈ 4 tests
$50
≈ 20 tests
$100
≈ 41 tests
| Model | Category | Price |
|---|---|---|
| Tokens | Input tokens | $2.4 1M tokens |
| Output tokens | $12 1M tokens |
Why reAPI
Drop-in access for a balanced Claude model
The Claude Sonnet 4.6 API speaks OpenAI Chat Completions verbatim. Moving an OpenAI integration to a balanced Claude route is a base URL, an API key, and a model-string change — not a platform rewrite. The native Anthropic /v1/messages surface is also available for SDK callers that prefer it.
Fast latency for live UX
Claude Sonnet 4.6 is tuned for production throughput: faster time-to-first-token than Opus on identical prompts, predictable streaming, and lower variance across calls. The right default when latency shows up in your user-experience metrics.
One key across GPT, Claude, and Gemini
A single api.reapi.ai key unlocks Claude Sonnet 4.6 alongside Claude Opus 4.7, GPT-5.5, Gemini 3.1 Pro, and every other frontier chat model on the platform. Compare vendors, add fallbacks, and route per call with a configuration change instead of an integration project.
Ship the Claude Sonnet 4.6 API in three steps
- step 01
Create an account and key on api.reapi.ai
Sign up at api.reapi.ai, open the console, generate an API key under API Keys, and top up tokens under Top Up. The chat workspace is separate from the reapi.ai image/video gateway — keys do not cross over.
Open - step 02
Send your first request
POST https://api.reapi.ai/v1/chat/completions with `model: "claude-sonnet-4-6"`, your `messages` array, and `max_tokens` set generously. The endpoint uses the standard chat-completions format, including streamed responses; the native Anthropic /v1/messages format works too.
Open - step 03
Route by complexity
Use Claude Sonnet 4.6 as your default chat route. Send the hardest reasoning, large refactors, or long-context analysis to Claude Opus 4.7 on the same key — flip the `model` field, the rest of the integration stays the same.
Open
docs/api/claude-sonnet-4-6
curl https://api.reapi.ai/v1/chat/completions \
-H "Authorization: Bearer YOUR_API_KEY" \
-H "Content-Type: application/json" \
-d '{
"model": "claude-sonnet-4-6",
"group": "default",
"messages": [
{ "role": "user", "content": "Hello" }
],
"stream": true,
"max_tokens": 4096,
"temperature": 0.7
}'Parameter validation failed
Rejected synchronously with the failing field named. Check enum values, ranges, and URL fields — nothing is charged.
Authentication or balance issue
401 means a missing or invalid Bearer key; 402 means the reserve exceeds your balance. Manage keys and credits in the console.
Content or material rejected
Reference material and outputs pass automated moderation. Rejected tasks fail with a clear error and a full refund.
Task failed or timed out
A task that reaches a failed state is never charged — the reserve refunds automatically. Keep the task id and retry when ready.
Frequently asked questions
Common questions about this model.
Claude Sonnet 4.6 is billed pay-as-you-go in USD against your api.reapi.ai token balance — see the pricing card on this page for the live per-1M-token rate. Failed requests are not charged.
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start building
Ready to ship?
Try it in the playground or grab an API key to integrate now.