What is Claude Opus 4.1?
Claude Opus 4.1 was Anthropic's most powerful model when it launched in August 2025. It represented the top of Anthropic's model family at that point, before being succeeded by Opus 4.5 in November 2025 and Opus 4.6 in February 2026. As of 2026, Opus 4.1 remains available but Anthropic recommends migrating to Opus 4.6 or Sonnet 4.6 for new projects, as both offer better performance at lower cost.
Claude Opus 4.1 Capabilities
Opus 4.1 was the first Anthropic model to demonstrate truly reliable performance on complex, multi-step tasks requiring deep reasoning. It scored above 75% on SWE-bench Verified at launch — making it the strongest coding model available at the time — and showed exceptional performance on scientific reasoning, legal analysis, and long-form writing.
The model supports a 200,000 token context window, vision input, and extended thinking — Anthropic's chain-of-thought reasoning mode where the model works through problems step by step before producing a final answer. This made it particularly useful for tasks requiring careful analysis rather than quick responses.
Claude Opus 4.1 Pricing
At launch, Opus 4.1 was priced at $15 per million input tokens and $75 per million output tokens — among the most expensive models in the market. This pricing was dramatically reduced with Opus 4.5 in November 2025, which dropped to $5/$25 per million tokens while exceeding Opus 4.1 performance. For new projects, using Sonnet 4.6 ($3/$15) or Opus 4.6 ($5/$25) is more cost-effective than Opus 4.1.
Should You Still Use Claude Opus 4.1?
For most use cases, no. Claude Sonnet 4.6 (released February 2026) is now preferred over Opus 4.1 on coding benchmarks at nearly 80% lower cost. The only reason to use Opus 4.1 today would be existing production systems that are already optimised for it and where migration risk outweighs the cost savings. Anthropic plans to deprecate Opus 4.1 on June 15, 2026.
Frequently Asked Questions
Is Claude Opus 4.1 still available?
Yes, but it is deprecated on June 15, 2026. Anthropic recommends migrating to Claude Opus 4.6 (claude-opus-4-6) for maximum capability or Claude Sonnet 4.6 (claude-sonnet-4-6) for the best price-performance balance.
What replaced Claude Opus 4.1?
Claude Opus 4.5 (November 2025) was the direct successor, offering better performance at one-third the cost. Claude Opus 4.6 (February 2026) is the current flagship, adding 1M context and improved agentic capabilities.