Anthropic exposes Claude Sonnet 4.5 through model ID claude-sonnet-4-5. Use the setup steps, sourced pricing, capabilities, and official provider links below to validate this route before deployment.
Last refreshed 2026-07-26. Next refresh: weekly.
Quick Start
- 1
- 2Use the Anthropic SDK or REST API to call
claude-sonnet-4-5— see the documentation for request format. - 3
Code Examples
Install
pip install anthropicAPI key
ANTHROPIC_API_KEYModel ID
claude-sonnet-4-5Use the versioned model ID, e.g. "claude-sonnet-4-6" or "claude-opus-4-7-20251101".
import anthropic
client = anthropic.Anthropic() # reads ANTHROPIC_API_KEY from env
message = client.messages.create(
model="claude-sonnet-4-5",
max_tokens=1024,
messages=[{"role": "user", "content": "Hello"}]
)
print(message.content[0].text)Pricing on Anthropic
| Type | Price (per 1M) |
|---|---|
| Input tokens | $3.00 |
| Output tokens | $15.00 |
Capabilities
VisionMultimodalReasoningJSON / Tool useStructured Outputs
About Claude Sonnet 4.5
Claude Sonnet 4.5 is Anthropic's Claude 4.5 model with multimodal text and image input and an optional reasoning mode. It offers a 200K-token context window and scores 86 on MMLU PRO.
Model Specs
Released2025-09-29
Context200k
ArchitectureDecoder Only
Knowledge cutoff2025-12