# Claude Opus 4 vs Llama 3.1 405B Instruct

As of Oct 14, 2026, Claude Opus 4 leads Llama 3.1 405B Instruct in 1 of 2 shared categories: Science.

Claude Opus 4: price per 1M tokens is unset in the catalog.

Llama 3.1 405B Instruct: price per 1M tokens is unset in the catalog.

Claude Opus 4: closed weights.

Llama 3.1 405B Instruct: open weights.

- Which to pick, General LLM: As of Oct 14, 2026, Llama 3.1 405B Instruct leads Claude Opus 4 in General LLM at #3 against #102.
- Which to pick, Science: As of Oct 14, 2026, Claude Opus 4 leads Llama 3.1 405B Instruct in Science at #91 against #124.

As of Oct 14, 2026, Claude Opus 4 is a former state-of-the-art holder in Reasoning (since Jun 3, 2025; sources LMArena Text (style-controlled, hard prompts); methodology v1.0).

As of Oct 14, 2026, Llama 3.1 405B Instruct is a former state-of-the-art holder in General LLM (since Aug 28, 2024; sources LMArena Text (style-controlled, overall); methodology v1.0).