Claude Opus 4.6 vs Grok 3

Claude Opus 4.6

Anthropic

Claude Opus 4.6, released by Anthropic in February 2026, is a large language model from the Claude 4 family designed for complex agent orchestration, extended reasoning, and long-form code generation. It features a 200K token context window (extendable to 1M tokens in beta), 128K maximum output tokens, native image understanding, and extended thinking with both standard and adaptive effort modes. Opus 4.6 targets multi-step agentic workflows, parallel tool use, and applications requiring sustained reasoning over large contexts.

Grok 3

xAI

Grok 3, released by xAI in February 2025, is a large language model trained on xAI's Colossus supercluster with substantially increased compute over previous generations. It features a 1M token context window, RL-enhanced Think mode for extended reasoning, and demonstrated strong results on mathematics, coding, and scientific benchmarks. Grok 3 targets complex reasoning, real-time information tasks via X platform integration, and agentic workflows via the xAI API.