# gpt-oss-120b vs Grok 4.3

> Grok 4.3 is the stronger model overall, scoring 43.6 to 36.0 on the Noometry Index. gpt-oss-120b costs 22× less per token, which makes it the better buy when Grok 4.3's lead doesn't matter for your workload.

- Canonical page: https://noometry.com/compare/gpt-oss-120b-vs-grok-4-3
- Last updated: 2026-10-10
- Shared benchmarks: 28

## Summary

- They share 28 benchmarks with published results for both. gpt-oss-120b scores higher in 1 category and Grok 4.3 in 8 categories; 9 gaps are clear of the uncertainty.
- The widest gap is in agentic & tool use, where Grok 4.3 leads 27.6 to 12.1.
- The biggest single-benchmark swing is LMCA: 22.1% for gpt-oss-120b and 38.3% for Grok 4.3.
- gpt-oss-120b is cheaper at $0.037 / $0.17 per million input/output tokens, against $1.25 / $2.50 for Grok 4.3.
- Grok 4.3 accepts more context: 1M tokens versus 131K.
- gpt-oss-120b has downloadable open weights; the other is API-only.

## Snapshot

| | gpt-oss-120b | Grok 4.3 |
|---|---|---|
| Provider | OpenAI | xAI |
| Noometry Index | 36.0 | 43.6 |
| Rank | 210 | 80 |
| Context | 131K | 1M |
| Input $/M | $0.037 | $1.25 |
| Output $/M | $0.17 | $2.50 |
| Weights | Open | Proprietary |

## Coding

- gpt-oss-120b: 33.2 (#251)
- Grok 4.3: 41.3 (#117)

| Benchmark | gpt-oss-120b | Grok 4.3 |
|---|---|---|
| SciCode | 36% | 47.3% |
| WeirdML | 48.2% | 49.9% |
| LMArena Coding | 1380 | 1415 |
| ALE-Bench | 575.62 | 944.17 |
| SWE-bench Verified (bash only) | 26% | — |
| Aider Polyglot | 41.8% | — |
| LMArena WebDev | — | 1357 |
| AlgoTune | 1.41 | — |

## Agentic & Tool Use

- gpt-oss-120b: 12.1 (#145)
- Grok 4.3: 27.6 (#93)

| Benchmark | gpt-oss-120b | Grok 4.3 |
|---|---|---|
| Vending-Bench 2 | -21.53 | 35.26 |
| Terminal-Bench | 18.7% | — |
| APEX-Agents | 4.4% | — |
| GDP.pdf | — | 8% |
| LMArena Search | — | 1165 |
| METR Time Horizons | 56.6% | — |

## Reasoning

- gpt-oss-120b: 19.5 (#236)
- Grok 4.3: 34.9 (#60)

| Benchmark | gpt-oss-120b | Grok 4.3 |
|---|---|---|
| CritPt | 1.1% | 8% |
| Chess Puzzles | 20% | 25% |
| LMArena Hard Prompts | 1364 | 1397 |
| DTBench | 76.3% | 90.7% |
| LMCA | 22.1% | 38.3% |
| Epoch Capabilities Index | 139.94 | 149.13 |
| SimpleBench | 22.1% | — |
| Kagi LLM Benchmark | 58.6% | — |
| NYT Connections (extended) | — | 55.2% |
| Mystery Game Puzzles | 2% | — |
| Surface Evolver Bench | 25% | — |
| ForecastBench | — | 60.3 |

## Math

- gpt-oss-120b: 50.6 (#43)
- Grok 4.3: 45.8 (#60)

| Benchmark | gpt-oss-120b | Grok 4.3 |
|---|---|---|
| OTIS Mock AIME 2024-2025 | 88.9% | 93.3% |
| LMArena Math | 1388 | 1388 |
| FrontierMath (Tiers 1-3) | — | 42.8% |
| FrontierMath Tier 4 | — | 14.6% |
| ProofBench | — | 11% |
| Omni-MATH | 68.8% | — |

## Knowledge

- gpt-oss-120b: 42.3 (#89)
- Grok 4.3: 52.5 (#57)

| Benchmark | gpt-oss-120b | Grok 4.3 |
|---|---|---|
| GPQA Diamond | 75.8% | 88.8% |
| LMArena Expert | 1356 | 1385 |
| SimpleQA Verified | — | 33.2% |
| MMLU-Pro | 79.5% | — |
| Confabulations | 15.7% | — |
| Vectara Hallucination Rate | 14.2% | — |
| GPQA (HELM) | 68.4% | — |

## Multimodal

- gpt-oss-120b: —
- Grok 4.3: 31.6 (#96)

| Benchmark | gpt-oss-120b | Grok 4.3 |
|---|---|---|
| LMArena Vision | — | 1231 |
| Blueprint-Bench 2 | — | 0% |

## Multilingual

- gpt-oss-120b: 48.2 (#142)
- Grok 4.3: 50.7 (#114)

| Benchmark | gpt-oss-120b | Grok 4.3 |
|---|---|---|
| LMArena Non-English | 1350 | 1385 |
| LMArena Chinese | 1384 | 1423 |
| LMArena French | 1370 | 1412 |
| LMArena German | 1355 | 1395 |
| LMArena Japanese | 1332 | 1379 |
| LMArena Korean | 1283 | 1357 |
| LMArena Russian | 1343 | 1399 |
| LMArena Spanish | 1388 | 1402 |

## Instruction Following

- gpt-oss-120b: 69.5 (#168)
- Grok 4.3: 72.3 (#135)

| Benchmark | gpt-oss-120b | Grok 4.3 |
|---|---|---|
| LMArena Instruction Following | 1318 | 1366 |
| IFEval | 83.6% | — |

## Long Context

- gpt-oss-120b: 31.4 (#273)
- Grok 4.3: 42.5 (#118)

| Benchmark | gpt-oss-120b | Grok 4.3 |
|---|---|---|
| LMArena Longer Query | 1319 | 1393 |
| Fiction.LiveBench | 44.4% | — |

## Writing & Preference

- gpt-oss-120b: 46.7 (#213)
- Grok 4.3: 58.6 (#112)

| Benchmark | gpt-oss-120b | Grok 4.3 |
|---|---|---|
| LMArena Text | 1366 | 1397 |
| LMArena Creative Writing | 1274 | 1380 |
| LMArena Multi-Turn | 1340 | 1406 |
| Short-Story Creative Writing | 77.1% | — |
| EQ-Bench Creative Writing | 961 | — |
| WildBench | 84.5% | — |
| EQ-Bench 4 | — | 1075 |

## FAQ

### Is gpt-oss-120b better than Grok 4.3?

Grok 4.3 is the stronger model overall, scoring 43.6 to 36.0 on the Noometry Index. gpt-oss-120b costs 22× less per token, which makes it the better buy when Grok 4.3's lead doesn't matter for your workload.

### Which is cheaper, gpt-oss-120b or Grok 4.3?

gpt-oss-120b is cheaper. It lists at $0.037 per million input tokens and $0.17 per million output tokens; Grok 4.3 lists at $1.25 and $2.50.

### Is gpt-oss-120b or Grok 4.3 better for coding?

Grok 4.3 scores higher on coding benchmarks: 41.3 versus 33.2 in the Noometry coding category.

### Which has the bigger context window?

Grok 4.3 does, with 1M tokens against 131K.

### How many benchmarks do gpt-oss-120b and Grok 4.3 share?

28 benchmarks have published results for both models. gpt-oss-120b has 48 scored results on Noometry and Grok 4.3 has 40.