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Anthropic

Claude Sonnet 4.5 on Anthropic

Claude 4.5 · Anthropic

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Last refreshed 2026-05-19. Next refresh: weekly.

Why use Claude Sonnet 4.5 on Anthropic?

Anthropic offers Claude Sonnet 4.5 with pay-as-you-go pricing at $3.00/1M input tokens. Anthropic is a safety-focused AI research company and creator of the Claude model family, offering API access through the Anthropic Console for text generation, analysis, and coding tasks.

Compare Claude Sonnet 4.5 across 7 providers to find the best fit for your use case
Input / 1M
$3.00
Output / 1M
$15.00
Cache
Not sourced
Batch
-50% · in $1.50 / out $7.50

Setup recipe

Python + curl
Install
pip install anthropic
Auth
export ANTHROPIC_API_KEY=...
Call
import anthropic
client = anthropic.Anthropic()  # reads ANTHROPIC_API_KEY from env
message = client.messages.create(
    model="claude-sonnet-4-5",
Model ID
claude-sonnet-4-5

Request example

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)

Gotchas

  • Use the versioned model ID, e.g. "claude-sonnet-4-6" or "claude-opus-4-7-20251101".
  • The examples expect ANTHROPIC_API_KEY; rename it only if your application config maps the new variable.

Compare Claude Sonnet 4.5 Across Providers

ProviderInput (per 1M)Output (per 1M)
Microsoft Foundry$3.00$15.00
Anthropic$3.00$15.00
Snowflake Cortex
GCP Vertex AI$3.00$15.00
AWS Bedrock$9.00$45.00
View all 7 providers →

Pricing

TypePrice (per 1M)
Input tokens$3.00
Output tokens$15.00

Capabilities

VisionMultimodalReasoningFunction CallingTool 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.

FAQ

What does Claude Sonnet 4.5 cost on Anthropic?

On Anthropic, Claude Sonnet 4.5 costs $3 per 1M input tokens and $15 per 1M output tokens.

What is the context window for Claude Sonnet 4.5 on Anthropic?

Claude Sonnet 4.5 supports a 200,000 token context window on Anthropic.

How does Anthropic compare to other Claude Sonnet 4.5 providers?

Claude Sonnet 4.5 is available from 7 providers. The cheapest input pricing is $3/1M tokens from Microsoft Foundry.

Who created Claude Sonnet 4.5?

Claude Sonnet 4.5 was created by Anthropic as part of the Claude 4.5 model family.

Is Claude Sonnet 4.5 open source?

Claude Sonnet 4.5's open source status is unknown in the seed data.

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