# DeepSeek V3.1 (Reasoning) vs GPT-OSS 120B

> Side-by-side benchmark comparison for DeepSeek V3.1 (Reasoning) and GPT-OSS 120B across agentic, coding, multimodal, knowledge, reasoning, multilingual, and math tasks.

- Canonical page: https://benchlm.ai/compare/deepseek-v3-1-reasoning-vs-gpt-oss-120b
- Last updated: October 17, 2026

- Shared sourced benchmarks: 4
- HTML indexing: indexable
- Ranking lane: BenchAlign v5.8

## Quick Verdict

DeepSeek V3.1 (Reasoning) leads by point estimate. Conditional score ranges do not establish rank confidence. Choose using the category evidence and your own workload tests.

## Summary

- DeepSeek V3.1 (Reasoning) has the higher overall point estimate 39.18 to 37.32. Conditional score ranges do not establish rank confidence.
- The clearest category separation is in instruction following, where the averages are 48.4 for DeepSeek V3.1 (Reasoning) and 84.3 for GPT-OSS 120B.
- The biggest single benchmark swing is AIME 2025 in Mathematics, with scores of 88.4% and 92.5%.

## Model Snapshot

| Property | DeepSeek V3.1 (Reasoning) | GPT-OSS 120B |
|----------|----------|----------|
| Creator | DeepSeek | OpenAI |
| Type | Open Weight | Open Weight |
| Reasoning | Reasoning | Non-Reasoning |
| Context | 128K | 128K |
| Overall Score | 39.18 | 37.32 |
| Benchmarks Covered | 6 | 8 |
| Pricing (input/output) | $0.00 / $0.00 | $0.00 / $0.00 |

## Category Breakdown

### Agentic

- Winner: Not comparable
- DeepSeek V3.1 (Reasoning) public-lane score: Coming soon
- GPT-OSS 120B public-lane score: 19.5 (Estimated · #110/128)

| Benchmark | DeepSeek V3.1 (Reasoning) | GPT-OSS 120B | Winner |
|-----------|-----------|-----------|--------|
| Gert Labs | Coming soon | 29.61% | Coming soon |

### Coding

- Winner: Not comparable
- DeepSeek V3.1 (Reasoning) public-lane score: Coming soon
- GPT-OSS 120B public-lane score: 23 (Estimated · #111/150)

| Benchmark | DeepSeek V3.1 (Reasoning) | GPT-OSS 120B | Winner |
|-----------|-----------|-----------|--------|
| LiveCodeBench | 74.8% | Coming soon | Coming soon |
| SWE-bench Verified | Coming soon | 62.4% | Coming soon |
| React Native Evals | Coming soon | 71.6% | Coming soon |

### Reasoning

- Winner: Not comparable
- DeepSeek V3.1 (Reasoning) public-lane score: 64.8 (Unranked · 2 rankable rows)
- GPT-OSS 120B public-lane score: 61.6 (Unranked · 2 rankable rows)

### Knowledge

- Winner: DeepSeek V3.1 (Reasoning)
- DeepSeek V3.1 (Reasoning) public-lane score: 40.7 (Supported · #116/184)
- GPT-OSS 120B public-lane score: 38.6 (Supported · #122/184)

| Benchmark | DeepSeek V3.1 (Reasoning) | GPT-OSS 120B | Winner |
|-----------|-----------|-----------|--------|
| GPQA | 80.1% | 80.1% | Tie |
| MMLU-Pro | 84.8% | Coming soon | Coming soon |
| HLE | 15.9% | 14.9% | DeepSeek V3.1 (Reasoning) |
| MMLU | Coming soon | 90% | Coming soon |

### Instruction Following

- Winner: Directional only
- DeepSeek V3.1 (Reasoning) public-lane score: 48.4 (#95/148)
- GPT-OSS 120B public-lane score: 84.3 (#50/148)

### Mathematics

- Winner: Not comparable
- DeepSeek V3.1 (Reasoning) public-lane score: Coming soon
- GPT-OSS 120B public-lane score: Coming soon

| Benchmark | DeepSeek V3.1 (Reasoning) | GPT-OSS 120B | Winner |
|-----------|-----------|-----------|--------|
| AIME 2024 | 93.1% | 95.8% | GPT-OSS 120B |
| AIME 2025 | 88.4% | 92.5% | GPT-OSS 120B |

## FAQ

### Which is better overall, DeepSeek V3.1 (Reasoning) or GPT-OSS 120B?

DeepSeek V3.1 (Reasoning) has the higher overall point estimate. Conditional score ranges do not establish rank confidence.

### Where is the biggest gap between DeepSeek V3.1 (Reasoning) and GPT-OSS 120B?

The widest category gap is in instruction following, where the averages are 48.4 for DeepSeek V3.1 (Reasoning) and 84.3 for GPT-OSS 120B.

### How many benchmarks does DeepSeek V3.1 (Reasoning) cover on BenchLM?

DeepSeek V3.1 (Reasoning) currently has 6 sourced benchmark scores on BenchLM.

### How many benchmarks does GPT-OSS 120B cover on BenchLM?

GPT-OSS 120B currently has 8 sourced benchmark scores on BenchLM.

## Related Comparisons

- [DeepSeek V3.1 (Reasoning) vs DeepSeek V3.1](/compare/deepseek-v3-1-vs-deepseek-v3-1-reasoning)
- [GPT-OSS 120B vs DeepSeek V3.1](/compare/deepseek-v3-1-vs-gpt-oss-120b)
- [DeepSeek V3.1 (Reasoning) vs GPT-OSS 20B](/compare/deepseek-v3-1-reasoning-vs-gpt-oss-20b)
- [GPT-OSS 120B vs GPT-OSS 20B](/compare/gpt-oss-120b-vs-gpt-oss-20b)

## Explore More

- [DeepSeek V3.1 (Reasoning) profile](/models/deepseek-v3-1-reasoning)
- [GPT-OSS 120B profile](/models/gpt-oss-120b)
- [Compare Pricing](/llm-pricing)
- [Alternative Finder](/tools/alternative-finder)
- [LLM Selector](/tools/llm-selector)
- [Overall Rankings](/best/overall)