# Claude Opus 5.5 vs DeepSeek V4.1 Flash

As of Oct 14, 2026, Claude Opus 5.5 leads DeepSeek V4.1 Flash in 8 of 8 shared categories: General LLM, Reasoning, Science, Coding › Web dev, Long context, Vision, Factuality, and Abstraction (ARC).

Claude Opus 5.5: $8.000000000000002 per 1M blended tokens.

DeepSeek V4.1 Flash: $0.16319999999999998 per 1M blended tokens.

Claude Opus 5.5: closed weights.

DeepSeek V4.1 Flash: open weights.

- Which to pick, General LLM: As of Oct 14, 2026, Claude Opus 5.5 leads DeepSeek V4.1 Flash in General LLM at #2 against #29.
- Which to pick, Reasoning: As of Oct 14, 2026, Claude Opus 5.5 leads DeepSeek V4.1 Flash in Reasoning at #1 against #27.
- Which to pick, Science: As of Oct 14, 2026, Claude Opus 5.5 leads DeepSeek V4.1 Flash in Science at #31 against #36.
- Which to pick, Coding › Web dev: As of Oct 14, 2026, Claude Opus 5.5 leads DeepSeek V4.1 Flash in Coding › Web dev at #1 against #19.
- Which to pick, Long context: As of Oct 14, 2026, Claude Opus 5.5 leads DeepSeek V4.1 Flash in Long context at #1 against #32.
- Which to pick, Vision: As of Oct 14, 2026, Claude Opus 5.5 leads DeepSeek V4.1 Flash in Vision at #4 against #21.
- Which to pick, Factuality: As of Oct 14, 2026, Claude Opus 5.5 leads DeepSeek V4.1 Flash in Factuality at #1 against #22.
- Which to pick, Abstraction (ARC): As of Oct 14, 2026, Claude Opus 5.5 leads DeepSeek V4.1 Flash in Abstraction (ARC) at #1 against #8.

As of Oct 14, 2026, Claude Opus 5.5 is tied for state of the art in Reasoning (since Oct 2, 2026; sources LMArena Text (style-controlled, hard prompts); methodology v1.0).

As of Oct 14, 2026, DeepSeek V4.1 Flash is state of the art on best per dollar in General LLM (since Oct 14, 2026; sources LMArena Text (style-controlled, overall); methodology v1.0).