claude-sonnet-4-5-20250929

Claude Sonnet 4.5

Anthropic's mid-sized model for powering real-world agents, with capabilities in coding, computer use, cybersecurity, and working with office files like spreadsheets.
Reasoning
Speed
Price
$2.00 • $10.00
Input
Output

Claude Sonnet 4.5 is the best coding model in the world. It’s the strongest model for building complex agents. It’s the best model at using computers. And it shows substantial gains in reasoning and math.

1000000 context window
64000 max output tokens
January 2025 knowledge cutoff
Reasoning token support

Modalities

Text

Input and output

Image

Input only

Audio

Not supported

Video

Not supported

Endpoints

Chat Completions

v1/chat/completions

Responses

v1/responses

Realtime

v1/realtime

Assistants

v1/assistants

Batch

v1/batch

Fine-tuning

v1/fine-tuning

Embeddings

v1/embeddings

Image generation

v1/images/generations

Videos

v1/videos

Image edit

v1/images/edits

Speech generation

v1/audio/speech

Transcription

v1/audio/transcriptions

Translation

v1/audio/translations

Moderation

v1/moderations

Completions (legacy)

v1/completions

Features

Streaming

Supported

Function calling

Supported

Structured outputs

Supported

Fine-tuning

Not supported

Distillation

Not supported

Tools

Tools supported by this model when using the Responses API.

Web search

Not supported

File search

Not supported

Image generation

Not supported

Code interpreter

Not supported

Computer use

Not supported

MCP

Not supported