Claude Opus 4.6 & Sonnet 4.6 Model Specification Sheet

Core Specifications

Developer: Anthropic
Model Family: Claude 4.6 Series
Primary Models: Claude Opus 4.6 & Claude Sonnet 4.6
Release Dates: Opus 4.6 — February 5, 2026; Sonnet 4.6 — February 17, 2026
Model Purpose: Frontier reasoning (Opus) and versatile reasoning + production workflows (Sonnet)

API Model IDs: claude-opus-4-6, claude-sonnet-4-6 ([platform docs](https://platform.claude.com/docs/en/about-claude/models/whats-new-claude-4-6))
Context Window: 200K tokens (standard), up to 1M tokens (beta on API)
Maximum Output Tokens: Opus 4.6 — up to 128K; Sonnet 4.6 — ~64K
Thinking Modes: Adaptive thinking, extended thinking, and context compaction features

Opus 4.6: Flagship intelligence for deep reasoning, agentic planning, and enterprise coding (state-of-the-art benchmark results across coding and agents) ([Anthropic news](https://www.anthropic.com/news/claude-opus-4-6))
Sonnet 4.6: Balanced, high-performance model with strong coding, computer use, professional reasoning, and extended workflows at lower cost than Opus ([Anthropic news](https://www.anthropic.com/news/claude-sonnet-4-6))
Long-context Reasoning: Both models support very large context inputs, enabling processing of entire projects, documents, and codebases.
Benchmarks: Opus 4.6 leads on advanced agentic coding benchmarks; Sonnet 4.6 delivers near-Opus performance on many real-world tasks at mid-tier cost.

Opus 4.6: Complex codebase refactoring, financial/legal analysis, multicore agent workflows, enterprise automation
Sonnet 4.6: Coding, spreadsheet automation, browser tasks, knowledge workflows, content generation, tool integration
Shared Abilities: Support for autonomous workflows, tool use, long reasoning sessions, and professional content creation

Sonnet 4.6 Pricing: ~$3 per million input tokens and $15 per million output tokens (same as predecessor) ([Anthropic docs](https://www.anthropic.com/claude/sonnet))
Opus 4.6 Pricing: ~$5 per million input tokens and $25 per million output tokens
Access: Available via Claude.ai, Claude Cowork, Claude Code, and the Claude API; supported on major cloud platforms
Free & Pro Tiers: Sonnet 4.6 is default on Free and Pro plans

1M token context window currently in beta on API — default standard limits remain lower
Pricing may vary by cloud provider and region
Sonnet 4.6 trades peak frontier power for cost efficiency relative to Opus 4.6

Claude Opus 4.6 expands enterprise reasoning with improved benchmarks and agent teams
Claude Sonnet 4.6 brings near-flagship performance at mid-tier pricing
Both models emphasize enhanced long-context reasoning and professional tool integration