Claude Opus 4.5 Paid

Claude Opus 4.5 is Anthropic’s late-2025 flagship model, aimed squarely at software engineering. It runs a 200K-token context window by default, supports 64K-token outputs, and Anthropic cut the price to $5 per million input tokens — down from $15 on Opus 4.1.

What is Claude Opus 4.5?

It is the top tier of the Claude 4.5 family, sitting above Sonnet 4.5 and Haiku 4.5. Anthropic markets it for agents that run for hours: refactoring across a repo, chasing a failing test, then opening a pull request without a human babysitting each step.

The API model ID is claude-opus-4-5. It is available in Claude.ai, the Anthropic API, Amazon Bedrock and Google Vertex AI.

What are Claude Opus 4.5’s main features?

• Extended thinking: visible reasoning traces you can budget with a token cap.
• 200K context, expandable: larger windows available on request for enterprise tiers.
• Agent Skills: reusable folders of instructions and scripts the model loads on demand.
• Computer use: drives a browser or desktop through screenshots and clicks.
• Effort control: a low/medium/high dial trades cost for depth.

Product Highlights

• The price cut is the headline — same class of model at a third of the old input cost.
• Excellent at long, messy engineering tasks; mediocre at very cheap high-volume classification.
• No free tier. Pro is $20/month, Max starts at $100/month for heavier agent use.

What is Claude Opus 4.5 used for?

1. Multi-file refactors inside a real repository.
2. Debugging flaky tests that need repeated runs and log reading.
3. Building agents with Claude Code or the Agent SDK.
4. Contract and policy review where a missed clause matters.
5. Browser automation through the computer-use tool.

Quick Summary

• Claude Opus 4.5 is Anthropic’s flagship model, released in November 2025.
• Input pricing is $5/M tokens, output $25/M tokens.
• The default context window is 200,000 tokens.
• It has no free tier; Claude Pro costs $20/month.
• Best for coding agents, overkill for simple chat or bulk tagging.