# Claude Opus 4.5 vs O3 Mini

As of Oct 15, 2026, Claude Opus 4.5 leads O3 Mini in 4 of 5 shared categories: Reasoning, Science, Long context, and Abstraction (ARC).

Claude Opus 4.5: $10 per 1M blended tokens.

O3 Mini: $1.9250000000000003 per 1M blended tokens.

Claude Opus 4.5: closed weights.

O3 Mini: closed weights.

- Which to pick, General LLM: As of Oct 15, 2026, O3 Mini leads Claude Opus 4.5 in General LLM at #10 against #41.
- Which to pick, Reasoning: As of Oct 15, 2026, Claude Opus 4.5 leads O3 Mini in Reasoning at #30 against #172.
- Which to pick, Science: As of Oct 15, 2026, Claude Opus 4.5 leads O3 Mini in Science at #68 against #76.
- Which to pick, Long context: As of Oct 15, 2026, Claude Opus 4.5 leads O3 Mini in Long context at #20 against #186.
- Which to pick, Abstraction (ARC): As of Oct 15, 2026, Claude Opus 4.5 leads O3 Mini in Abstraction (ARC) at #49 against #51.

As of Oct 15, 2026, Claude Opus 4.5 is a former state-of-the-art holder in Reasoning (since Dec 1, 2025; sources LMArena Text (style-controlled, hard prompts); methodology v1.0).

As of Oct 15, 2026, O3 Mini is a former state-of-the-art holder in Reasoning (since Feb 9, 2025; sources LMArena Text (style-controlled, hard prompts); methodology v1.0).