Skip to content

Model detail

Claude Opus 4.6

Provided by Anthropic
Pay-as-you-go

Opus 4.6 is Anthropic’s strongest model for coding and long-running professional tasks. It is built for agents that operate across entire workflows rather than single prompts, making it especially effective for large codebases, complex refactors, and multi-step debugging that unfolds over time. The model shows deeper contextual understanding, stronger problem decomposition, and greater reliability on hard engineering tasks than prior generations. Beyond coding, Opus 4.6 excels at sustained knowledge work. It produces near-production-ready documents, plans, and analyses in a single pass, and maintains coherence across very long outputs and extended sessions. This makes it a strong default for tasks that require persistence, judgment, and follow-through, such as technical design, migration planning, and end-to-end project execution. For users upgrading from earlier Opus versions, see our [official migration guide here](https://openrouter.ai/docs/guides/guides/model-migrations/claude-4-6-opus)

Model specs

Model ID
claude-opus-4-6
Context length
1M
Max output
128K
I/O modalities
Released
2026-02

02

API endpoints

One MixRoute gateway, OpenAI-compatible

  • Anthropic Messages /v1/messages POST
  • OpenAI-compatible /v1/chat/completions POST
  • Gemini /v1beta/models/{model}:generateContent POST

03

Pricing

Flat rate, unit: /1M Tokens

Input

$5.0000 /1M Tokens

Completion

$25.0000 /1M Tokens

Cache read

$0.5000 /1M Tokens

Cache creation

$6.2500 /1M Tokens

05

Selection summary

Quickly judge whether it fits your workload

What is this model good for?

Coding and long-running professional tasks end-to-end

Use Opus 4.6 for large codebases, complex refactors, and multi-step debugging. It excels at sustained knowledge work, producing near-production-ready documents, plans, and analyses in a single pass.

What should you check before using it?

Test on hard engineering and knowledge work tasks

Opus 4.6 shows deeper contextual understanding and stronger problem decomposition. Test your most demanding engineering tasks and verify the quality of sustained knowledge work outputs. Knowledge cutoff: 2025-05.

Why use it through MixRoute?

Claude Opus 4.6 takes text and images on one route

Text and image inputs share the same route and the same key. MixRoute serves Claude Opus 4.6 on the OpenAI-compatible endpoint /v1/chat/completions; point your existing client at https://api.mixroute.ai/v1 with the model ID claude-opus-4-6 and re-run your integration tests.

07

Capabilities & compatibility

Unconfirmed capabilities stay "Unknown," no guesses

Available:

Tool calling

Claude Opus 4.6 supports function and tool calls.

EX Send a tools definition; the response returns tool_calls to execute and feed results back.
Available:

Structured output

Claude Opus 4.6 can produce JSON-formatted output on demand.

EX response_format: { type: "json_schema" } forces valid JSON output.
Available:

Streaming

Claude Opus 4.6 supports streamed responses.

EX stream: true streams tokens incrementally, so chat UIs render as they arrive.
Available:

Prompt caching

Claude Opus 4.6 supports prompt caching under supported routing conditions.

EX Keep the system prompt and tool definitions at the start of the request; repeated prefixes are automatically billed at the cache-read rate.
Available:

Vision input

Claude Opus 4.6 can process image inputs alongside text.

EX Pass a base64-encoded image in a image_url content part alongside text messages.
Available:

OpenAI SDK

Call Claude Opus 4.6 through MixRoute's OpenAI-compatible endpoint.

EX Change base_url to https://api.mixroute.ai/v1; everything else follows the OpenAI style.

08

Token cost estimator

Live estimate from this page's pricing, not an actual bill

Share of the same prefix read repeatedly, up to 100%

09

FAQ

claude-opus-4-6 supports up to 128000 output tokens per request. Plan your prompts to stay within this limit, and use the max_tokens or max_completion_tokens parameter to control output length.

One endpoint, a testable decision

Test this model and alternate routes with the same request format

Start from a real workload, then let quality, total cost, and failure conditions decide whether to send production traffic.