Where do I create an API key and buy tokens?

Both happen on api.reapi.ai — the chat workspace runs as its own platform separate from the image / video task gateway at reapi.ai. Sign up at api.reapi.ai, generate a key under API Keys, and top up under Top Up. A reapi.ai/settings/apikeys key will not authenticate against the chat endpoint.

Is the Claude Sonnet 4.6 API OpenAI-compatible?

Yes. The Claude Sonnet 4.6 API is a drop-in for OpenAI's /v1/chat/completions — same request shape, same `messages` array, same `stream` / `temperature` / `top_p` / `max_tokens` parameters, same SSE wire format. Most teams migrate by changing the base URL to https://api.reapi.ai/v1, swapping the API key, and setting `model: "claude-sonnet-4-6"`. The native Anthropic Messages format at /v1/messages is also available.

What is the Claude Sonnet 4.6 context window?

Claude Sonnet 4.6 has a 1M token context window and supports up to 128K output tokens per response. Long inputs stream in one call; chunking is rarely needed.

When should I pick Claude Sonnet 4.6 over Claude Opus 4.7?

Pick Sonnet 4.6 for the default chat route, code review, mid-complexity agents, and production traffic where latency and throughput matter. Pick Opus 4.7 for high-stakes coding, large refactors, complex multi-step agents, and long-context analysis where output quality dominates the decision. Both share the same endpoint and OpenAI-compatible wire format — switching is a one-line change in the `model` field.

Does Claude Sonnet 4.6 support vision and tool use?

Yes. Claude Sonnet 4.6 accepts text and image inputs in the same call, and supports standard OpenAI tool calling (`tools`, `tool_choice`, `parallel_tool_calls`) plus the native Anthropic tool-use spec when called via /v1/messages.

What is the `group` parameter?

`group` selects a token group on the api.reapi.ai gateway, which routes the request to a specific channel pool. `default` is the standard pool and covers nearly every workload. You can leave the field out of the body if you're happy with the default routing.

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 OpenAI-compatible /v1/chat/completions for high-volume production traffic that doesn't need Opus-tier reasoning on every call.

Price

Input tokens$2/ 1M tokens

Output tokens$10/ 1M tokens

Get API key View API docs

02use cases

What you can build

Real workflows powered by this model.

Claude Sonnet 4.6 driving live customer-support conversations

01/case

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

Claude Sonnet 4.6 reviewing a pull request diff

02/case

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.

Claude Sonnet 4.6 orchestrating a mid-complexity agent workflow

03/case

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.

03pricing

Pricing

Credit-based — 1 credit = $0.001 USD. Pay only for completed generations.

Category	Unit	Price
Tokens
Input tokens	1M tokens	$2
Output tokens	1M tokens	$10

05why

Why reAPI

OpenAI-compatible drop-in 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.

07quickstart

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 is OpenAI-compatible, 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

08faq

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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10api reference

docs/api/claude-sonnet-4-6

API reference

Drop-in code and the full parameter table.

View full reference

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
  }'

start building

Ready to ship?

Try it in the playground or grab an API key to integrate now.

Get API key Get API key

What you can build

Real workflows powered by this model.

01/case