# Claude Opus 5.5 vs DeepSeek V4 Flash High Preview

As of Oct 15, 2026, Claude Opus 5.5 leads DeepSeek V4 Flash High Preview in 5 of 5 shared categories: General LLM, Reasoning, Coding › Web dev, Long context, and Factuality.

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

DeepSeek V4 Flash High Preview: price per 1M tokens is unset in the catalog.

Claude Opus 5.5: closed weights.

DeepSeek V4 Flash High Preview: open weights.

- Which to pick, General LLM: As of Oct 15, 2026, Claude Opus 5.5 leads DeepSeek V4 Flash High Preview in General LLM at #2 against #89.
- Which to pick, Reasoning: As of Oct 15, 2026, Claude Opus 5.5 leads DeepSeek V4 Flash High Preview in Reasoning at #1 against #94.
- Which to pick, Coding › Web dev: As of Oct 15, 2026, Claude Opus 5.5 leads DeepSeek V4 Flash High Preview in Coding › Web dev at #1 against #71.
- Which to pick, Long context: As of Oct 15, 2026, Claude Opus 5.5 leads DeepSeek V4 Flash High Preview in Long context at #1 against #84.
- Which to pick, Factuality: As of Oct 15, 2026, Claude Opus 5.5 leads DeepSeek V4 Flash High Preview in Factuality at #1 against #97.

As of Oct 15, 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 15, 2026, DeepSeek V4 Flash High Preview is ranked #71 in Coding › Web dev (since Oct 15, 2026; sources LMArena WebDev; methodology v1.0).