Claude Sonnet 4 overview

Provider

The company that provides the model

Anthropic

Context window

The number of tokens you can send in a prompt

200k tokens

Maximum output

The maximum number of tokens a model can generate in one request

64,000 tokens

Input token cost

The cost of prompt tokens sent to the model

$3.00 / 1M input tokens

Output token cost

The cost of output tokens generated by the model

$1500 / 1M output tokens

Knowledge cut-off date

When the model's knowledge ends

March 1, 2025
Unknown

Release date

When the model was launched

May 22, 2025

Claude Sonnet 4 functionality

Function (tool calling) support

Capability for the model to use external tools

Yes

Vision support

Ability to process and analyze visual inputs, like images

Yes

Multilingual

Support for multiple languages

Yes

Fine-tuning

Whether the model supports fine-tuning on custom datasets

Yes - only through direct engagement with Anthropic

Common questions about Claude Sonnet 4

What is Claude Sonnet 4?

Claude Sonnet 4 is Anthropic’s high-performance reasoning model, optimized for complex, multi-step tasks with robust chain-of-thought capabilities.

How much does Claude Sonnet 4 cost?

It costs $3.00 per million input tokens and $1,500.00 per million output tokens.

What is the context window for Claude Sonnet 4?

Claude Sonnet 4 supports a context window of up to 200,000 tokens.

What is the maximum output length for Claude Sonnet 4?

It can generate up to 64,000 tokens in a single response.

When was Claude Sonnet 4 released?

Claude Sonnet 4 was released on May 22, 2025.

How recent is the training data for Claude Sonnet 4?

Its knowledge cut-off date is March 1, 2025.

Does Claude Sonnet 4 support vision capabilities?

Yes, Claude Sonnet 4 supports vision inputs and analysis.

Can Claude Sonnet 4 perform tool calling or functions?

Yes, it supports function calling and structured outputs.

Is Claude Sonnet 4 multilingual?

Yes, it can handle input and output in multiple languages.

Does Claude Sonnet 4 support fine-tuning?

Yes—but only through direct engagement with Anthropic.

Where can I find the official documentation for Claude Sonnet 4?

You can view the model comparison table and full details here.

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