Claude Sonnet 4.5

anthropic/claude-sonnet-4-5

Previous generation Sonnet with strong all-around performance. Consider migrating to Sonnet 4.6.

Specifications

Context Window 200K tokens

Context (Beta) 1M tokens

Max Output 64K tokens

Latency fast

Knowledge Cutoff Jan 2025

Training Data Jul 2025

Pricing

Input $3.00 per 1M tokens

Output $15.00 per 1M tokens

Capabilities

text Text generation and understanding

vision Image and visual input processing

tool use Function calling and tool integration

extended thinking Deep reasoning with chain-of-thought

API Identifiers

Model ID anthropic/claude-sonnet-4-5

Provider API ID claude-sonnet-4-5-20250929

AWS Bedrock anthropic.claude-sonnet-4-5-20250929-v1:0

GCP Vertex AI claude-sonnet-4-5@20250929

Usage via Multi-Router

curl https://api.multi-router.ai/v1/chat/completions \
  -H "Authorization: Bearer YOUR_API_KEY" \
  -H "Content-Type: application/json" \
  -H "x-mr-router-id: YOUR_ROUTER_ID" \
  -d '{
    "model": "anthropic/claude-sonnet-4-5",
    "messages": [
      {"role": "user", "content": "Hello!"}
    ]
  }'