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LLMS • CURATED • UPDATED NOV 24, 2025

Claude Opus 4.5

First Claude model with the effort parameter and context compaction

Anthropic's Opus-tier model announced on November 24, 2025, introducing the effort parameter for balancing capability against cost, context compaction, and a deeper memory tool. Available across the Anthropic API, Amazon Bedrock, Google Cloud Vertex AI, and Microsoft Foundry.

Pricing Enterprise
Platforms web, api
API Yes
Open Source No
Modalities LLMs, IDEs & Coding Tools
Best For Best for Cost-Capability Tradeoffs
Date Added 2025-11-24

Opus 4.5 was the first Claude model to ship the effort parameter, an important capability evolution before Opus 4.6 and 4.7.

Website
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Enterprise

Enterprise pricing — contact Claude Opus 4.5 for a custom quote and contract terms.

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Q

Is Claude Opus 4.5 free?

A

Claude Opus 4.5 is offered as an enterprise solution; contact the provider for pricing.

Q

Does Claude Opus 4.5 have an API?

A

Yes, Claude Opus 4.5 offers an API for programmatic integration.

Q

What is Claude Opus 4.5 best for?

A

Claude Opus 4.5 is best for Cost-Capability Tradeoffs. Anthropic's Opus-tier model announced on November 24, 2025, introducing the effort parameter for balancing capability against cost, context compaction, and a deeper memory tool. Opus 4.5 was the first Claude model to ship the effort parameter, an important capability evolution before Opus 4.6 and 4.7.

Q

What platforms does Claude Opus 4.5 support?

A

Claude Opus 4.5 supports web, api.

Q

Is Claude Opus 4.5 open source?

A

No, Claude Opus 4.5 is not open source.

Q

How do I use Claude Opus 4.5?

A

Claude Opus 4.5 is a large language model for text generation, analysis, and conversation. Access through the web interface. Enter prompts or questions to get responses.

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