How do you start calling Claude Sonnet 5?

Use the model ID claude-sonnet-5 through the compatible chat completions endpoint. Select the reasoning effort level (low, medium, high, max, or x-high) appropriate for your task.

Can you call Claude Sonnet 5 with the SDK you already use?

Yes. Sonnet 5 is served through a compatible endpoint. You can continue using your existing SDK by changing the base URL and model ID.

What is the max output length for claude-sonnet-5?

claude-sonnet-5 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.

When was Claude Sonnet 5 released, and is it still maintained?

Claude Sonnet 5 was released on 2026-06-30. Its catalog status is stable. Check the model page for deprecation notices before you build a long-lived integration on it.

Does Claude Sonnet 5 support tool calling and structured output?

Confirm the current capabilities in the model documentation. Sonnet 5 is designed for agentic workflows and professional work. Test with your specific tool definitions.

How should you set the output budget for claude-sonnet-5?

For claude-sonnet-5, set the max_tokens or max_completion_tokens parameter to control spending per call. Start with a budget aligned to your typical response length and increase only when longer outputs are genuinely needed. Monitor token usage in the API response headers to tune your budget over time.

Does claude-sonnet-5 have a free tier?

Claude Sonnet 5 is billed per use and the record publishes no free-tier allowance. The current published rates are input $2.0000 per 1M tokens and output $10.0000 per 1M tokens. Trial credit or promotional quota is tied to your account rather than to the model, so check the console before planning around a free tier.

Model detail

Claude Sonnet 5

Provided by Anthropic

Pay-as-you-go

Sonnet 5 is Anthropic's most capable Sonnet-class model, with frontier performance across coding, agents, and professional work. It supports adaptive thinking with selectable reasoning effort levels (low, medium, high, max, and x-high), a 1M-token context window, and text, image, and file inputs. Sonnet 5 uses an updated tokenizer and includes real-time cyber safeguards that block certain high-risk dual-use activities.

Model specs

Model ID: claude-sonnet-5

Context length: 1M
Max output: 128K
I/O modalities
Released: 2026-06

API endpoints

One MixRoute gateway, OpenAI-compatible

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

Pricing

Flat rate, unit: /1M Tokens

Input

$2.0000 /1M Tokens

Completion

$10.0000 /1M Tokens

Cache read

$0.2000 /1M Tokens

Cache creation

$2.5000 /1M Tokens

Selection summary

Quickly judge whether it fits your workload

What is this model good for?

Frontier coding, agents, and professional work

Use Sonnet 5 for coding, agentic workflows, and professional tasks. It supports adaptive thinking with selectable reasoning effort levels, a 1M-token context window, and text/image/file inputs.

What should you check before using it?

Tune reasoning effort and review safety safeguards

Sonnet 5 offers five reasoning effort levels (low to x-high). Test your workload at the appropriate level. Note that real-time cyber safeguards block certain high-risk dual-use activities. Knowledge cutoff: 2026-01.

Why use it through MixRoute?

Claude Sonnet 5 takes text and images on one route

Text and image inputs share the same route and the same key. MixRoute serves Claude Sonnet 5 on the OpenAI-compatible endpoint /v1/chat/completions; point your existing client at https://api.mixroute.ai/v1 with the model ID claude-sonnet-5 and re-run your integration tests.

Capabilities & compatibility

Unconfirmed capabilities stay "Unknown," no guesses

Tool calling

Claude Sonnet 5 supports function and tool calls.

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

Structured output

Claude Sonnet 5 can produce JSON-formatted output on demand.

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

Streaming

Claude Sonnet 5 supports streamed responses.

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

Prompt caching

Claude Sonnet 5 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.

Vision input

Claude Sonnet 5 can process image inputs alongside text.

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

OpenAI SDK

Call Claude Sonnet 5 through MixRoute's OpenAI-compatible endpoint.

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

Token cost estimator

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

Input tokens Max per request 1M

Output tokens Max per request 128K

Requests / month

Cache hit rate 0%

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

FAQ

Compare claude-sonnet-5 against models of similar capability and pricing on your actual workload. Evaluate latency, output quality, instruction following, and cost per task. Run side-by-side tests with your own prompts — the best model depends on your specific use case, not just benchmark scores.

Get started

01

Create an API key

Generate a key in the Console; one key calls every model.
02

Set the base URL

Fully OpenAI SDK-compatible; just swap the URL to connect.

https://api.mixroute.ai/v1
03

Specify the model ID

In the request's model field, enter:

claude-sonnet-5

Create an API key

New users get $5 in free credits

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.

Create an API key View integration docs