Claude Opus 4.6 and Sonnet 4.6: Anthropic's February Blitz

Anthropic released two major models in February 2026. Claude Opus 4.6, launched on February 5th, achieves 80.8% on SWE-bench Verified — the highest score at the time of release for any AI model on real-world software engineering tasks. Two weeks later, Claude Sonnet 4.6 followed with 79.6% on the same benchmark, at one-fifth the price.

Both models support a 1 million token context window in beta, a 5x increase over the previous 200K limit. This enables processing of entire codebases, legal document sets, and research corpora in a single pass. Opus 4.6 introduces "agent teams" — the ability to coordinate multiple Claude instances on complex, multi-step workflows.

Opus 4.6 is priced at $5.00 per million input tokens and $25.00 per million output tokens, a significant reduction from the previous Opus generation. Sonnet 4.6 maintains the same $3.00/$15.00 pricing as its predecessor while delivering substantially better performance. In head-to-head comparisons, users preferred Sonnet 4.6 over Sonnet 4.5 in 70% of tests.

The rapid-fire releases suggest Anthropic is accelerating its development cadence, moving from annual flagship releases to multiple major updates per quarter. For developers, the practical takeaway is that Claude Sonnet 4.6 now offers the best value proposition in the market — near-frontier performance at mid-tier pricing.