Anthropic's most powerful AI model. Built for complex analysis, expert-level reasoning, and tasks demanding the highest quality output. Free, no login.
Claude Opus 4 is Anthropic's flagship AI model, purpose-built for tasks requiring the deepest reasoning and most nuanced understanding. It excels at expert-level analysis across law, science, medicine, engineering, and complex business problems.
Opus 4 offers the largest context window in the Claude family, the most sophisticated reasoning chains, and the highest accuracy on demanding benchmarks. It's the model of choice when quality and depth matter more than speed.
Yes — you can use Claude Opus 4 for free on chat-gpt.org. No sign-up or login needed.
Opus 4 is more powerful for complex reasoning tasks, while Sonnet 4 offers a better speed-to-quality balance for everyday use.
Complex analysis, expert-level research, advanced coding, long document processing, and tasks requiring maximum accuracy.
Opus 4 prioritizes quality over speed, so it may take slightly longer but delivers superior results on complex tasks.
Yes — Opus 4 has the largest context window in the Claude family and excels at processing lengthy texts.
Claude Opus was created by Anthropic, an AI safety company focused on building reliable, helpful AI.