# DeepSeek V4 Flash 0731 vs GPT-5.5

> Side-by-side benchmark comparison for DeepSeek V4 Flash 0731 and GPT-5.5 across agentic, coding, multimodal, knowledge, reasoning, multilingual, and math tasks.

- Canonical page: https://benchlm.ai/compare/deepseek-v4-flash-0731-vs-gpt-5-5
- Last updated: September 18, 2026

- Shared sourced benchmarks: 15
- HTML indexing: indexable
- Ranking lane: BenchAlign v5

## Quick Verdict

Pick GPT-5.5 if you want the stronger benchmark profile. DeepSeek V4 Flash 0731 only makes more sense when its price, context window, or workload-specific category wins matter more than the overall score.

## Summary

- GPT-5.5 leads overall 71.86 to 56.
- The clearest category separation is in mathematics, where the averages are 79.9 for DeepSeek V4 Flash 0731 and 69.4 for GPT-5.5.
- The biggest single benchmark swing is Terminal-Bench 2.0 in Agentic, with scores of 56.9% and 82%.
- DeepSeek V4 Flash 0731 is the cheaper option on output tokens, which matters if you expect large responses or heavy interactive use.

## Model Snapshot

| Property | DeepSeek V4 Flash 0731 | GPT-5.5 |
|----------|----------|----------|
| Creator | DeepSeek | OpenAI |
| Type | Proprietary | Proprietary |
| Reasoning | Reasoning | Reasoning |
| Context | 1M | 1M |
| Overall Score | null | 71.86 |
| Benchmarks Covered | 40 | 39 |
| Pricing (input/output) | $0.14 / $0.28 | $5.00 / $30.00 |

## Category Breakdown

### Agentic

- Winner: Coming soon
- DeepSeek V4 Flash 0731 public-lane score: Coming soon
- GPT-5.5 public-lane score: 62.2 (Supported · #14/154)

| Benchmark | DeepSeek V4 Flash 0731 | GPT-5.5 | Winner |
|-----------|-----------|-----------|--------|
| Terminal-Bench 2.0 | 56.9% | 82% | GPT-5.5 |
| BrowseComp | 73.2% | 84.4% | GPT-5.5 |
| HLE w/ tools | 45.1% | Coming soon | Coming soon |
| MCP Atlas | 69% | 75.3% | GPT-5.5 |
| Toolathlon | 47.8% | 55.6% | GPT-5.5 |
| Terminal-Bench 2.1 | 82.7% | Coming soon | Coming soon |
| CyberGym | 76.7% | 81.8% | GPT-5.5 |
| Toolathlon-Verified | 70.3% | Coming soon | Coming soon |
| Agents' Last Exam | 25.2% | Coming soon | Coming soon |
| AutomationBench | 25.1% | Coming soon | Coming soon |
| Terminal-Bench 2.1 (Vals) | 67.0% | 76.4% | GPT-5.5 |
| OSWorld-Verified | Coming soon | 78.7% | Coming soon |
| τ²-bench results | Coming soon | 98% | Coming soon |
| Gert Labs | Coming soon | 72.93% | Coming soon |
| ResearchClawBench | Coming soon | 17.0% | Coming soon |
| OSWorld 2.0 | Coming soon | 13.0% | Coming soon |
| JobBench | Coming soon | 42.7% | Coming soon |
| ExploitGym | Coming soon | 13.4% | Coming soon |
| ApprenticeBench | Coming soon | 20% | Coming soon |

### Coding

- Winner: Coming soon
- DeepSeek V4 Flash 0731 public-lane score: Coming soon
- GPT-5.5 public-lane score: 67.5 (Supported · #7/154)

| Benchmark | DeepSeek V4 Flash 0731 | GPT-5.5 | Winner |
|-----------|-----------|-----------|--------|
| LiveCodeBench Pass@1-COT | 91.6% | Coming soon | Coming soon |
| Codeforces | 3052.0 | Coming soon | Coming soon |
| SWE-bench Verified | 79% | Coming soon | Coming soon |
| SWE-bench Pro | 52.6% | 58.6% | GPT-5.5 |
| SWE Multilingual | 73.3% | Coming soon | Coming soon |
| Terminal-Bench 2.0 | 56.9% | 82.0% | GPT-5.5 |
| Terminal-Bench 2.1 | 82.7% | Coming soon | Coming soon |
| NL2Repo | 54.2% | Coming soon | Coming soon |
| DeepSWE | 54.4% | Coming soon | Coming soon |
| DSBench-FullStack | 68.7% | Coming soon | Coming soon |
| DSBench-Hard | 59.6% | Coming soon | Coming soon |
| VulcanBench v3 | 88.4% | Coming soon | Coming soon |
| OpenHarmony Bench | 53.8% | Coming soon | Coming soon |
| LiveCodeBench (Vals) | 87.3% | 85.3% | DeepSeek V4 Flash 0731 |
| SWE-bench (Vals) | 88.8% | 82.6% | DeepSeek V4 Flash 0731 |
| Vibe Code Bench | Coming soon | 69.85% | Coming soon |
| React Native Evals | Coming soon | 84.7% | Coming soon |
| cursorBench31 | Coming soon | 59.2% | Coming soon |
| cursorBench32 | Coming soon | 58.4% | Coming soon |
| FrontierCode 1.1 Main | Coming soon | 43.0% | Coming soon |

### Multimodal & Grounded

- Winner: Coming soon
- DeepSeek V4 Flash 0731 public-lane score: Coming soon
- GPT-5.5 public-lane score: 71.4 (#19/48)

| Benchmark | DeepSeek V4 Flash 0731 | GPT-5.5 | Winner |
|-----------|-----------|-----------|--------|
| MMMU-Pro | Coming soon | 81.2% | Coming soon |
| MMMU-Pro w/ Python | Coming soon | 83.2% | Coming soon |
| OfficeQA Pro | Coming soon | 54.1% | Coming soon |

### Reasoning

- Winner: Coming soon
- DeepSeek V4 Flash 0731 public-lane score: Coming soon
- GPT-5.5 public-lane score: 64 (#13/20)

| Benchmark | DeepSeek V4 Flash 0731 | GPT-5.5 | Winner |
|-----------|-----------|-----------|--------|
| MRCR 1M | 78.7% | Coming soon | Coming soon |
| CorpusQA 1M | 60.5% | Coming soon | Coming soon |
| MRCR v2 64K-128K | Coming soon | 83.1% | Coming soon |
| MRCR v2 128K-256K | Coming soon | 87.5% | Coming soon |
| ARC-AGI-2 | Coming soon | 85% | Coming soon |
| ARC-AGI-3 | Coming soon | 0.4% | Coming soon |

### Knowledge

- Winner: Coming soon
- DeepSeek V4 Flash 0731 public-lane score: Coming soon
- GPT-5.5 public-lane score: 72.7 (Supported · #7/184)

| Benchmark | DeepSeek V4 Flash 0731 | GPT-5.5 | Winner |
|-----------|-----------|-----------|--------|
| MMLU-Pro | 86.2% | Coming soon | Coming soon |
| SimpleQA | 34.1% | Coming soon | Coming soon |
| Chinese-SimpleQA | 78.9% | Coming soon | Coming soon |
| GPQA | 88.1% | 93.6% | GPT-5.5 |
| GPQA-D | 88.1% | 93.6% | GPT-5.5 |
| HLE | 34.8% | 52.2% | GPT-5.5 |
| GPQA Diamond (Vals) | 89.9% | 93.2% | GPT-5.5 |
| MMLU-Pro (Vals) | 86.2% | 88.1% | GPT-5.5 |
| HLE w/o tools | Coming soon | 41.4% | Coming soon |

### Instruction Following

- Winner: Coming soon
- DeepSeek V4 Flash 0731 public-lane score: Coming soon
- GPT-5.5 public-lane score: 91.9 (#7/124)

### Mathematics

- Winner: Coming soon
- DeepSeek V4 Flash 0731 public-lane score: 79.9 (Unranked · 4 rankable rows)
- GPT-5.5 public-lane score: 69.4 (Unranked · 3 rankable rows)

| Benchmark | DeepSeek V4 Flash 0731 | GPT-5.5 | Winner |
|-----------|-----------|-----------|--------|
| HMMT Feb 2026 | 94.8% | Coming soon | Coming soon |
| IMOAnswerBench | 88.4% | Coming soon | Coming soon |
| Apex | 33.0% | Coming soon | Coming soon |
| Apex Shortlist | 85.7% | Coming soon | Coming soon |
| FrontierMath (legacy) | Coming soon | 51.7% | Coming soon |
| FrontierMath v2 (Tiers 1-3) | Coming soon | 51.700% | Coming soon |
| FrontierMath v2 (Tier 4) | Coming soon | 35.400% | Coming soon |

## FAQ

### Which is better overall, DeepSeek V4 Flash 0731 or GPT-5.5?

GPT-5.5 is ahead overall on BenchLM right now.

### Where is the biggest gap between DeepSeek V4 Flash 0731 and GPT-5.5?

The widest category gap is in mathematics, where the averages are 79.9 for DeepSeek V4 Flash 0731 and 69.4 for GPT-5.5.

### How many benchmarks does DeepSeek V4 Flash 0731 cover on BenchLM?

DeepSeek V4 Flash 0731 currently has 40 sourced benchmark scores on BenchLM.

### How many benchmarks does GPT-5.5 cover on BenchLM?

GPT-5.5 currently has 39 sourced benchmark scores on BenchLM.

## Related Comparisons

- [DeepSeek V4 Flash 0731 vs GPT-5.5 Pro](/compare/deepseek-v4-flash-0731-vs-gpt-5-5-pro)
- [GPT-5.5 vs GPT-5.5 Pro](/compare/gpt-5-5-vs-gpt-5-5-pro)
- [DeepSeek V4 Flash 0731 vs Claude Fable 5.1](/compare/claude-fable-5-1-vs-deepseek-v4-flash-0731)
- [GPT-5.5 vs Claude Fable 5.1](/compare/claude-fable-5-1-vs-gpt-5-5)

## Explore More

- [DeepSeek V4 Flash 0731 profile](/models/deepseek-v4-flash-0731)
- [GPT-5.5 profile](/models/gpt-5-5)
- [Compare Pricing](/llm-pricing)
- [Alternative Finder](/tools/alternative-finder)
- [LLM Selector](/tools/llm-selector)
- [Overall Rankings](/best/overall)