Claude Opus 5.5: Features, Pricing and How to Access

What is Claude Opus 5.5?

Claude Opus 5.5 is an advanced artificial intelligence model developed by Anthropic. It is the initial model released in the Claude 5.5 family and performs at the level of Claude Fable 5.1 across most tasks.

Anthropic reports that Claude Opus 5.5 leads in agentic coding, computer use, and knowledge work. It was tested prior to launch by external evaluators, including METR and Frontier Design.

How much does Claude Opus 5.5 cost?

Claude Opus 5.5 costs $4 per million input tokens and $20 per million output tokens for standard API usage. This represents a 20 percent decrease in base token pricing compared to Claude Opus 5.

Cache reads cost $0.20 per million tokens, which Anthropic notes is a 60 percent drop from the previous generation. Cache writes are priced at $6.25 per million tokens.

For faster turnaround, Anthropic provides a Fast mode in Claude Code and the Claude Platform. Fast mode operates at up to 2.5 times the speed and costs $8 per million input tokens and $40 per million output tokens.

What are the key capabilities of Claude Opus 5.5?

Claude Opus 5.5 specializes in software engineering, large-scale codebase refactoring, and natural workplace communication. Anthropic states that its communication style places critical information up front, making outputs easier to review.

During early testing, the model completed a 680,000-line code migration in less than a day. In another test, Claude Opus 5.5 audited and corrected a 200,000-line codebase in under three hours, using 2.5 times fewer tokens than Claude Opus 5.

Anthropic also tested the model on translating HAProxy from C to Rust. Claude Opus 5.5 finished the task in 9.5 hours compared to 12 hours for Claude Fable 5.1, while cutting costs by 51 percent.

How to access Claude Opus 5.5

Claude Opus 5.5 is available through multiple official Anthropic channels and third-party partner integrations. Users can run the model depending on their subscription tier or developer environment.

• Anthropic user plans: Available on Claude Pro, Max, Team, and seat-based Enterprise subscriptions, which feature expanded five-hour limits and a savable rate limit reset.
• Developer tools: Available directly within Claude Code and the Claude Platform API, including the option to enable Fast mode.
• Microsoft Copilot: Available to subscribers holding a Copilot Premium plan, as reported by Geeky Gadgets.
• Verification programs: Accessible to qualified groups applying to Anthropic's Life Sciences Verification Program and Cyber Verification Program.

What safeguards and limits apply to Claude Opus 5.5?

Claude Opus 5.5 achieved the highest score to date on Anthropic's automated behavioral audit alignment suite. It shows greater resistance to prompt injection and is less likely to take hard-to-reverse actions without instruction.

Because its biology and cybersecurity capabilities match Claude Mythos 5.1, Anthropic restricts high-risk use behind vetting programs. When safety safeguards trigger during benchmarks, tasks fall back to Claude Opus 4.8 for cybersecurity and Claude Opus 5 for biology.

Frequently asked questions

Sources: Anthropic · Geeky Gadgets