# GPT-OSS 120B vs o3-mini

> Side-by-side benchmark comparison for GPT-OSS 120B and o3-mini across agentic, coding, multimodal, knowledge, reasoning, multilingual, and math tasks.

- Canonical page: https://benchlm.ai/compare/gpt-oss-120b-vs-o3-mini
- Last updated: September 10, 2026

- Shared sourced benchmarks: 0
- HTML indexing: indexable
- Ranking lane: BenchAlign v5

## Quick Verdict

No benchmark verdict yet: there is no shared sourced benchmark row for GPT-OSS 120B and o3-mini.

## Summary

- GPT-OSS 120B and o3-mini do not currently share a sourced benchmark row. The mirror therefore compares metadata, pricing, context windows, and each model's separately reported coverage without naming a benchmark winner.

## Model Snapshot

| Property | GPT-OSS 120B | o3-mini |
|----------|----------|----------|
| Creator | OpenAI | OpenAI |
| Type | Open Weight | Proprietary |
| Reasoning | Non-Reasoning | Reasoning |
| Context | 128K | 200K |
| Independent public score (not head-to-head) | 45.69 | 46.83 |
| Benchmarks Covered | 2 | 5 |
| Pricing (input/output) | $0.00 / $0.00 | $1.10 / $4.40 |

## Category Breakdown

### Agentic

- Winner: Insufficient shared evidence
- GPT-OSS 120B public-lane score: 40.8 (Estimated · #113/152)
- o3-mini public-lane score: Coming soon

| Benchmark | GPT-OSS 120B | o3-mini | Winner |
|-----------|-----------|-----------|--------|
| Gert Labs | 29.61% | Coming soon | Coming soon |

### Coding

- Winner: Insufficient shared evidence
- GPT-OSS 120B public-lane score: 43.5 (Estimated · #100/151)
- o3-mini public-lane score: 45.3 (Estimated · #88/151)

| Benchmark | GPT-OSS 120B | o3-mini | Winner |
|-----------|-----------|-----------|--------|
| React Native Evals | 71.6% | Coming soon | Coming soon |
| SWE-bench Verified | Coming soon | 49.3% | Coming soon |

### Reasoning

- Winner: Insufficient shared evidence
- GPT-OSS 120B public-lane score: 56.8 (Unranked · 2 rankable rows)
- o3-mini public-lane score: Coming soon

### Knowledge

- Winner: Insufficient shared evidence
- GPT-OSS 120B public-lane score: 42.2 (Estimated · #121/183)
- o3-mini public-lane score: 39.7 (Supported · #134/183)

| Benchmark | GPT-OSS 120B | o3-mini | Winner |
|-----------|-----------|-----------|--------|
| MMLU | Coming soon | 86.9% | Coming soon |
| GPQA | Coming soon | 77.2% | Coming soon |

### Instruction Following

- Winner: Insufficient shared evidence
- GPT-OSS 120B public-lane score: 84.3 (#47/123)
- o3-mini public-lane score: Coming soon

| Benchmark | GPT-OSS 120B | o3-mini | Winner |
|-----------|-----------|-----------|--------|
| IFEval | Coming soon | 93.9% | Coming soon |

### Mathematics

- Winner: Insufficient shared evidence
- GPT-OSS 120B public-lane score: Coming soon
- o3-mini public-lane score: Coming soon

| Benchmark | GPT-OSS 120B | o3-mini | Winner |
|-----------|-----------|-----------|--------|
| AIME 2024 | Coming soon | 87.3% | Coming soon |

## FAQ

### Can I compare GPT-OSS 120B and o3-mini on BenchLM yet?

Not fully yet. BenchLM is tracking both models, but sourced benchmark coverage is still incomplete for a fair score-level comparison.

### Why does this page show "coming soon" values?

BenchLM only calls winners when public benchmark coverage is available on both sides of the comparison.

## Related Comparisons

- [GPT-OSS 120B vs GPT-OSS 20B](/compare/gpt-oss-120b-vs-gpt-oss-20b)
- [o3-mini vs GPT-OSS 20B](/compare/gpt-oss-20b-vs-o3-mini)
- [GPT-OSS 120B vs o3](/compare/gpt-oss-120b-vs-o3)
- [o3-mini vs o3](/compare/o3-vs-o3-mini)

## Explore More

- [GPT-OSS 120B profile](/models/gpt-oss-120b)
- [o3-mini profile](/models/o3-mini)
- [Compare Pricing](/llm-pricing)
- [Alternative Finder](/tools/alternative-finder)
- [LLM Selector](/tools/llm-selector)
- [Overall Rankings](/best/overall)