Claude Opus 4.5 vs DeepSeek V4.1 Flash
As of Oct 15, 2026, Claude Opus 4.5 leads DeepSeek V4.1 Flash in 1 of 7 shared categories: Long context.
Claude Opus 4.5
It used to be. Was SOTA in Reasoning.
DeepSeek V4.1 Flash
Yes. Yes on General LLM (best per dollar); Reasoning (best per dollar). Not the overall leader.
| Category | Claude Opus 4.5 | DeepSeek V4.1 Flash |
|---|---|---|
| General LLM | #41 · #41 in General LLM Margin 21.808510638297875 LMArena leaderboard dataset · Oct 13, 2026 | #32 · #32 in General LLM Margin 17.02127659574468 LMArena leaderboard dataset · Oct 13, 2026 |
| Reasoning | #30 · Was SOTA · Reasoning Margin 16.489361702127653 LMArena leaderboard dataset · Oct 13, 2026 | #29 · #29 in Reasoning Margin 15.957446808510639 LMArena leaderboard dataset · Oct 13, 2026 |
| Math | #16 · #16 in Math Margin 33.33333333333333 Epoch AI benchmarking hub · Nov 24, 2025 | #— · Not enough data Margin — LMArena leaderboard dataset · Oct 13, 2026 |
| Science | #68 · #68 in Science Margin — Epoch AI benchmarking hub · Nov 24, 2025 | #36 · #36 in Science Margin — Epoch AI benchmarking hub · Sep 9, 2026 |
| Coding | #— · Not enough data Margin — LMArena leaderboard dataset · Oct 13, 2026 | #— · Not enough data Margin — LMArena leaderboard dataset · Oct 13, 2026 |
| Coding › Web dev | #58 · Was SOTA · Coding › Web dev Margin 45.6 LMArena leaderboard dataset · Oct 13, 2026 | #21 · #21 in Coding › Web dev Margin 16 LMArena leaderboard dataset · Oct 13, 2026 |
| Long context | #20 · Was SOTA · Long context Margin 10.63829787234043 LMArena leaderboard dataset · Oct 13, 2026 | #37 · #37 in Long context Margin 19.68085106382979 LMArena leaderboard dataset · Oct 13, 2026 |
| Vision | — | #21 · #21 in Vision Margin 57.89473684210526 Epoch AI benchmarking hub · Sep 9, 2026 |
| Factuality | #40 · #40 in Factuality Margin 23.837209302325576 LMArena leaderboard dataset · Oct 13, 2026 | #25 · #25 in Factuality Margin 15.116279069767444 LMArena leaderboard dataset · Oct 13, 2026 |
| Abstraction (ARC) | #49 · #49 in Abstraction (ARC) Margin — Epoch AI benchmarking hub · Nov 24, 2025 | #8 · #8 in Abstraction (ARC) Margin — Epoch AI benchmarking hub · Sep 9, 2026 |
Claude Opus 4.5: $10 per 1M blended tokens.
DeepSeek V4.1 Flash: $0.23463 per 1M blended tokens.
Claude Opus 4.5: closed weights.
DeepSeek V4.1 Flash: open weights.
General LLM: As of Oct 15, 2026, DeepSeek V4.1 Flash leads Claude Opus 4.5 in General LLM at #32 against #41.
Reasoning: As of Oct 15, 2026, DeepSeek V4.1 Flash leads Claude Opus 4.5 in Reasoning at #29 against #30.
Science: As of Oct 15, 2026, DeepSeek V4.1 Flash leads Claude Opus 4.5 in Science at #36 against #68.
Coding › Web dev: As of Oct 15, 2026, DeepSeek V4.1 Flash leads Claude Opus 4.5 in Coding › Web dev at #21 against #58.
Long context: As of Oct 15, 2026, Claude Opus 4.5 leads DeepSeek V4.1 Flash in Long context at #20 against #37.
Factuality: As of Oct 15, 2026, DeepSeek V4.1 Flash leads Claude Opus 4.5 in Factuality at #25 against #40.
Abstraction (ARC): As of Oct 15, 2026, DeepSeek V4.1 Flash leads Claude Opus 4.5 in Abstraction (ARC) at #8 against #49.
Claude Opus 4.5 · DeepSeek V4.1 Flash
Claude Opus 4.5 or DeepSeek V4.1 Flash?
As of Oct 15, 2026, Claude Opus 4.5 leads DeepSeek V4.1 Flash in 1 of 7 shared categories: Long context.
Claude Opus 4.5 or DeepSeek V4.1 Flash for General LLM?
As of Oct 15, 2026, DeepSeek V4.1 Flash leads Claude Opus 4.5 in General LLM at #32 against #41.
Claude Opus 4.5 or DeepSeek V4.1 Flash for Reasoning?
As of Oct 15, 2026, DeepSeek V4.1 Flash leads Claude Opus 4.5 in Reasoning at #29 against #30.
Claude Opus 4.5 or DeepSeek V4.1 Flash for Science?
As of Oct 15, 2026, DeepSeek V4.1 Flash leads Claude Opus 4.5 in Science at #36 against #68.