# GPT-6 Sol vs gpt-oss-20b

> GPT-6 Sol is the stronger model overall, scoring 49.2 to 32.1 on the Noometry Index. gpt-oss-20b costs 111× less per token, which makes it the better buy when GPT-6 Sol's lead doesn't matter for your workload.

- Canonical page: https://noometry.com/compare/gpt-6-sol-vs-gpt-oss-20b
- Last updated: 2026-10-10
- Shared benchmarks: 14

## Summary

- They share 14 benchmarks with published results for both. GPT-6 Sol scores higher in 8 categories and gpt-oss-20b in 1 category; 9 gaps are clear of the uncertainty.
- The widest gap is in writing & preference, where GPT-6 Sol leads 72.3 to 35.8.
- gpt-oss-20b is cheaper at $0.018 / $0.09 per million input/output tokens, against $2 / $10 for GPT-6 Sol.
- GPT-6 Sol accepts more context: 1.05M tokens versus 131K.
- gpt-oss-20b has downloadable open weights; the other is API-only.

## Snapshot

| | GPT-6 Sol | gpt-oss-20b |
|---|---|---|
| Provider | OpenAI | OpenAI |
| Noometry Index | 49.2 | 32.1 |
| Rank | 46 | 249 |
| Context | 1.05M | 131K |
| Input $/M | $2 | $0.018 |
| Output $/M | $10 | $0.09 |
| Weights | Proprietary | Open |

## Coding

- GPT-6 Sol: 59.6 (#11)
- gpt-oss-20b: 37.1 (#185)

| Benchmark | GPT-6 Sol | gpt-oss-20b |
|---|---|---|
| LMArena Coding | 1453 | 1307 |
| DeepSWE | 68.8% | — |
| FrontierCode | 49.3% | — |
| LMArena WebDev | 1692 | — |
| SciCode | — | 34.4% |
| WeirdML | — | 40.9% |
| ALE-Bench | — | 566.05 |

## Agentic & Tool Use

- GPT-6 Sol: 33.5 (#49)
- gpt-oss-20b: 9.2 (#146)

| Benchmark | GPT-6 Sol | gpt-oss-20b |
|---|---|---|
| Terminal-Bench | — | 3.4% |
| GDP.pdf | 28% | — |

## Reasoning

- GPT-6 Sol: 49.3 (#34)
- gpt-oss-20b: 18.8 (#251)

| Benchmark | GPT-6 Sol | gpt-oss-20b |
|---|---|---|
| LMArena Hard Prompts | 1420 | 1274 |
| Kagi LLM Benchmark | — | 53.2% |
| NYT Connections (extended) | 90.1% | — |
| CritPt | — | 1.4% |
| Chess Puzzles | — | 4% |
| EBR-Bench | 53.3% | — |
| DTBench | — | 68% |
| LMCA | — | 14.5% |
| Epoch Capabilities Index | — | 137.81 |

## Math

- GPT-6 Sol: 35.8 (#135)
- gpt-oss-20b: 37.6 (#93)

| Benchmark | GPT-6 Sol | gpt-oss-20b |
|---|---|---|
| LMArena Math | 1404 | 1317 |
| OTIS Mock AIME 2024-2025 | — | 65.3% |
| Omni-MATH | — | 56.5% |

## Knowledge

- GPT-6 Sol: 43.0 (#87)
- gpt-oss-20b: 34.6 (#186)

| Benchmark | GPT-6 Sol | gpt-oss-20b |
|---|---|---|
| LMArena Expert | 1449 | 1258 |
| GPQA Diamond | — | 60.8% |
| MMLU-Pro | — | 74% |
| Vectara Hallucination Rate | 6.5% | — |
| GPQA (HELM) | — | 59.4% |

## Multimodal

- GPT-6 Sol: 47.6 (#9)
- gpt-oss-20b: —

| Benchmark | GPT-6 Sol | gpt-oss-20b |
|---|---|---|
| Furniture Assembly | 58.3% | — |

## Multilingual

- GPT-6 Sol: 51.0 (#113)
- gpt-oss-20b: 42.4 (#192)

| Benchmark | GPT-6 Sol | gpt-oss-20b |
|---|---|---|
| LMArena Non-English | 1389 | 1269 |
| LMArena Chinese | 1416 | 1311 |
| LMArena Russian | 1407 | 1279 |
| LMArena Spanish | 1377 | 1267 |
| LMArena German | — | 1249 |
| LMArena Japanese | — | 1245 |
| LMArena Korean | — | 1239 |

## Instruction Following

- GPT-6 Sol: 74.4 (#97)
- gpt-oss-20b: 62.0 (#235)

| Benchmark | GPT-6 Sol | gpt-oss-20b |
|---|---|---|
| LMArena Instruction Following | 1406 | 1236 |
| IFEval | — | 73.2% |

## Long Context

- GPT-6 Sol: 43.2 (#100)
- gpt-oss-20b: 37.9 (#203)

| Benchmark | GPT-6 Sol | gpt-oss-20b |
|---|---|---|
| LMArena Longer Query | 1415 | 1251 |

## Writing & Preference

- GPT-6 Sol: 72.3 (#15)
- gpt-oss-20b: 35.8 (#260)

| Benchmark | GPT-6 Sol | gpt-oss-20b |
|---|---|---|
| LMArena Text | 1396 | 1288 |
| LMArena Creative Writing | 1392 | 1201 |
| EQ-Bench Creative Writing | 2125 | 666 |
| LMArena Multi-Turn | 1405 | 1268 |
| WildBench | — | 73.7% |

## FAQ

### Is GPT-6 Sol better than gpt-oss-20b?

GPT-6 Sol is the stronger model overall, scoring 49.2 to 32.1 on the Noometry Index. gpt-oss-20b costs 111× less per token, which makes it the better buy when GPT-6 Sol's lead doesn't matter for your workload.

### Which is cheaper, GPT-6 Sol or gpt-oss-20b?

gpt-oss-20b is cheaper. It lists at $0.018 per million input tokens and $0.09 per million output tokens; GPT-6 Sol lists at $2 and $10.

### Is GPT-6 Sol or gpt-oss-20b better for coding?

GPT-6 Sol scores higher on coding benchmarks: 59.6 versus 37.1 in the Noometry coding category.

### Which has the bigger context window?

GPT-6 Sol does, with 1.05M tokens against 131K.

### How many benchmarks do GPT-6 Sol and gpt-oss-20b share?

14 benchmarks have published results for both models. GPT-6 Sol has 22 scored results on Noometry and gpt-oss-20b has 34.