Claude Sonnet 5.5 vs DeepSeek V4.1 Flash 1017
As of Nov 3, 2026, Claude Sonnet 5.5 leads DeepSeek V4.1 Flash 1017 in 5 of 5 shared categories: General LLM, Science, Coding, Abstraction (ARC), and Legal.
Claude Sonnet 5.5
Yes. SOTA in Coding (tied), Coding › Agentic (tied), and Vision (tied).
DeepSeek V4.1 Flash 1017
Yes. Yes on Coding (best per dollar). Not the overall leader.
| Category | Claude Sonnet 5.5 | DeepSeek V4.1 Flash 1017 |
|---|---|---|
| General LLM | #17 · Near-SOTA · General LLM Margin 9.890109890109883 Vals AI · Nov 3, 2026 | #60 · #60 in General LLM Margin 33.421750663129984 Vals AI · Nov 3, 2026 |
| Reasoning | #19 · #19 in Reasoning Margin 11.904761904761898 LMArena leaderboard dataset · Oct 28, 2026 | #— · Not enough data Margin — Epoch AI benchmarking hub · Oct 17, 2026 |
| Math | #4 · #4 in Math Margin 6.666666666666671 Epoch AI benchmarking hub · Sep 28, 2026 | — |
| Science | #3 · #3 in Science Margin — Vals AI · Oct 30, 2026 | #17 · #17 in Science Margin — Epoch AI benchmarking hub · Oct 17, 2026 |
| Coding | #1 · Co-SOTA · Coding Margin 0 Terminal-Bench Harbor Hub · Nov 3, 2026 | #8 · #8 in Coding Margin 23.919753086419746 Vals AI · Nov 3, 2026 |
| Coding › Agentic | #1 · Co-SOTA · Coding › Agentic Margin 0 Terminal-Bench Harbor Hub · Oct 23, 2026 | — |
| Coding › Web dev | #3 · Near-SOTA · Coding › Web dev Margin 1.5625 LMArena leaderboard dataset · Oct 28, 2026 | — |
| Long context | #12 · #12 in Long context Margin 7.738095238095241 LMArena leaderboard dataset · Oct 28, 2026 | — |
| Vision | #1 · Co-SOTA · Vision Margin 0 Epoch AI benchmarking hub · Sep 28, 2026 | — |
| Factuality | #19 · #19 in Factuality Margin 11.65644171779141 LMArena leaderboard dataset · Oct 28, 2026 | #— · Not enough data Margin — Epoch AI benchmarking hub · Oct 17, 2026 |
| Abstraction (ARC) | #4 · #4 in Abstraction (ARC) Margin — Epoch AI benchmarking hub · Sep 28, 2026 | #8 · #8 in Abstraction (ARC) Margin — Epoch AI benchmarking hub · Oct 17, 2026 |
| Cybersecurity | #6 · #6 in Cybersecurity Margin 18.75 Vals AI · Oct 27, 2026 | — |
| Legal | #8 · #8 in Legal Margin — Vals AI · Nov 3, 2026 | #12 · #12 in Legal Margin — Vals AI · Nov 3, 2026 |
Which is better for coding?
As of Nov 3, 2026, Claude Sonnet 5.5 leads DeepSeek V4.1 Flash 1017 in Coding at #1 against #8. See the full coding ranking.
Pricing
Claude Sonnet 5.5: $4 per 1M blended tokens.
DeepSeek V4.1 Flash 1017: $0.52 per 1M blended tokens.
Claude Sonnet 5.5: closed weights.
DeepSeek V4.1 Flash 1017: open weights.
Benchmarks side by side
| Benchmark | Claude Sonnet 5.5 | DeepSeek V4.1 Flash 1017 |
|---|---|---|
| ARC-AGI | 96.5% | 94.5% |
| Code Migration | 86.9 | 67.5 |
| Excel Modeling Benchmark (EMB) | 75.9 | 69.2 |
| Finance Agent | 67.3 | 62.9 |
| GPQA Diamond | 95.6% | 93.2% |
| Legal Research Bench | 48.1 | 45.2 |
| SimpleQA Verified | 46.5% | 42.5% |
| Tax Agent Bench | 42.0 | 44.4 |
| Vals Index | 70.9 | 61.3 |
| Vibe Code Bench | 92.4 | 87.7 |
Latest validated result for each model. Benchmarks where only one model has a result are left out.
Verdict
As of Nov 3, 2026, Claude Sonnet 5.5 leads DeepSeek V4.1 Flash 1017 in 5 of 5 shared categories: General LLM, Science, Coding, Abstraction (ARC), and Legal.
General LLM: As of Nov 3, 2026, Claude Sonnet 5.5 leads DeepSeek V4.1 Flash 1017 in General LLM at #17 against #60.
Science: As of Nov 3, 2026, Claude Sonnet 5.5 leads DeepSeek V4.1 Flash 1017 in Science at #3 against #17.
Coding: As of Nov 3, 2026, Claude Sonnet 5.5 leads DeepSeek V4.1 Flash 1017 in Coding at #1 against #8.
Abstraction (ARC): As of Nov 3, 2026, Claude Sonnet 5.5 leads DeepSeek V4.1 Flash 1017 in Abstraction (ARC) at #4 against #8.
Legal: As of Nov 3, 2026, Claude Sonnet 5.5 leads DeepSeek V4.1 Flash 1017 in Legal at #8 against #12.
Claude Sonnet 5.5 · DeepSeek V4.1 Flash 1017
Claude Sonnet 5.5 or DeepSeek V4.1 Flash 1017?
As of Nov 3, 2026, Claude Sonnet 5.5 leads DeepSeek V4.1 Flash 1017 in 5 of 5 shared categories: General LLM, Science, Coding, Abstraction (ARC), and Legal.
Claude Sonnet 5.5 or DeepSeek V4.1 Flash 1017 for General LLM?
As of Nov 3, 2026, Claude Sonnet 5.5 leads DeepSeek V4.1 Flash 1017 in General LLM at #17 against #60.
Claude Sonnet 5.5 or DeepSeek V4.1 Flash 1017 for Science?
As of Nov 3, 2026, Claude Sonnet 5.5 leads DeepSeek V4.1 Flash 1017 in Science at #3 against #17.
Claude Sonnet 5.5 or DeepSeek V4.1 Flash 1017 for Coding?
As of Nov 3, 2026, Claude Sonnet 5.5 leads DeepSeek V4.1 Flash 1017 in Coding at #1 against #8.