# GPT-5.6 Luna vs Grok 4

> GPT-5.6 Luna is the stronger model overall, scoring 54.6 to 48.1 on the Noometry Index.

- Canonical page: https://noometry.com/compare/gpt-5-6-luna-vs-grok-4
- Last updated: 2026-10-12
- Shared benchmarks: 28

## Summary

- They share 28 benchmarks with published results for both. GPT-5.6 Luna scores higher in 8 categories and Grok 4 in 2 categories; 10 gaps are clear of the uncertainty.
- The widest gap is in math, where GPT-5.6 Luna leads 77.7 to 48.4.
- The biggest single-benchmark swing is ARC-AGI-2: 59.5% for GPT-5.6 Luna and 16% for Grok 4.

## Snapshot

| | GPT-5.6 Luna | Grok 4 |
|---|---|---|
| Provider | OpenAI | xAI |
| Noometry Index | 54.6 | 48.1 |
| Rank | 30 | 56 |
| Context | 1.05M | — |
| Input $/M | $0.20 | — |
| Output $/M | $1.20 | — |
| Weights | Proprietary | Proprietary |

## Coding

- GPT-5.6 Luna: 54.5 (#28)
- Grok 4: 50.3 (#46)

| Benchmark | GPT-5.6 Luna | Grok 4 |
|---|---|---|
| WeirdML | 60.9% | 45.7% |
| LMArena Coding | 1466 | 1408 |
| DeepSWE | 67.2% | — |
| FrontierCode | 39.8% | — |
| Aider Polyglot | — | 79.6% |
| CursorBench | 35.9% | — |
| LMArena WebDev | 1519 | — |
| SciCode | 53.6% | — |
| ALE-Bench | 1,667 | — |

## Agentic & Tool Use

- GPT-5.6 Luna: 34.4 (#45)
- Grok 4: 32.3 (#68)

| Benchmark | GPT-5.6 Luna | Grok 4 |
|---|---|---|
| BALROG | 45.6% | 43.6% |
| Terminal-Bench | — | 27.2% |
| APEX-Agents | 43% | — |
| Berkeley Function Calling Leaderboard | — | 63% |
| GDPval | — | 21.1% |
| Cybench | — | 43% |
| DeepResearch Bench | — | 47.3% |
| GDP.pdf | 22.7% | — |
| LMArena Search | — | 1142 |
| METR Time Horizons | — | 66.6% |
| Vending-Bench 2 | 4,095 | — |

## Reasoning

- GPT-5.6 Luna: 47.6 (#43)
- Grok 4: 36.7 (#65)

| Benchmark | GPT-5.6 Luna | Grok 4 |
|---|---|---|
| ARC-AGI-2 | 59.5% | 16% |
| SimpleBench | 46.8% | 60.5% |
| Kagi LLM Benchmark | 49.1% | 73.6% |
| ARC-AGI-1 | 88% | 66.7% |
| Chess Puzzles | 40% | 28% |
| LMArena Hard Prompts | 1451 | 1409 |
| Epoch Capabilities Index | 156.39 | 146.44 |
| NYT Connections (extended) | 69.4% | — |
| CritPt | 20.6% | — |
| Mystery Game Puzzles | 21% | — |
| DTBench | 89.1% | — |
| LMCA | 48.5% | — |
| Surface Evolver Bench | 61.9% | — |
| ForecastBench | — | 60.9 |

## Math

- GPT-5.6 Luna: 77.7 (#14)
- Grok 4: 48.4 (#64)

| Benchmark | GPT-5.6 Luna | Grok 4 |
|---|---|---|
| OTIS Mock AIME 2024-2025 | 98.3% | 84% |
| LMArena Math | 1458 | 1422 |
| FrontierMath (Tiers 1-3) | 82.1% | — |
| FrontierMath Tier 4 | 61% | — |
| ProofBench | 60% | — |
| Omni-MATH | — | 60.3% |
| FrontierMath (Feb 2025 set) | — | 19.7% |
| FrontierMath Tier 4 (v1) | — | 2.1% |

## Knowledge

- GPT-5.6 Luna: 58.5 (#34)
- Grok 4: 53.8 (#55)

| Benchmark | GPT-5.6 Luna | Grok 4 |
|---|---|---|
| GPQA Diamond | 91.6% | 87% |
| LMArena Expert | 1478 | 1415 |
| SimpleQA Verified | 41% | — |
| MMLU-Pro | — | 85.1% |
| Confabulations | — | 12.4% |
| GPQA (HELM) | — | 72.7% |

## Multimodal

- GPT-5.6 Luna: 42.7 (#28)
- Grok 4: 33.7 (#94)

| Benchmark | GPT-5.6 Luna | Grok 4 |
|---|---|---|
| LMArena Vision | 1258 | 1210 |
| GeoBench | — | 45% |
| Blueprint-Bench 2 | 22.6% | — |
| Furniture Assembly | 42.5% | — |
| LMArena Document | 1457 | — |

## Multilingual

- GPT-5.6 Luna: 52.8 (#78)
- Grok 4: 51.8 (#103)

| Benchmark | GPT-5.6 Luna | Grok 4 |
|---|---|---|
| LMArena Non-English | 1417 | 1403 |
| LMArena Chinese | 1470 | 1427 |
| LMArena French | 1456 | 1418 |
| LMArena German | 1454 | 1429 |
| LMArena Japanese | 1411 | 1394 |
| LMArena Korean | 1415 | 1377 |
| LMArena Russian | 1428 | 1410 |
| LMArena Spanish | 1448 | 1420 |

## Instruction Following

- GPT-5.6 Luna: 75.6 (#57)
- Grok 4: 79.2 (#5)

| Benchmark | GPT-5.6 Luna | Grok 4 |
|---|---|---|
| LMArena Instruction Following | 1437 | 1387 |
| IFEval | — | 94.9% |

## Long Context

- GPT-5.6 Luna: 43.9 (#82)
- Grok 4: 63.1 (#4)

| Benchmark | GPT-5.6 Luna | Grok 4 |
|---|---|---|
| LMArena Longer Query | 1436 | 1409 |
| Fiction.LiveBench | — | 94.4% |

## Writing & Preference

- GPT-5.6 Luna: 68.0 (#29)
- Grok 4: 58.5 (#116)

| Benchmark | GPT-5.6 Luna | Grok 4 |
|---|---|---|
| LMArena Text | 1431 | 1411 |
| LMArena Creative Writing | 1396 | 1397 |
| LMArena Multi-Turn | 1434 | 1416 |
| Short-Story Creative Writing | — | 76.9% |
| EQ-Bench Creative Writing | 1829 | — |
| WildBench | — | 79.7% |
| EQ-Bench 4 | 1156 | — |

## FAQ

### Is GPT-5.6 Luna better than Grok 4?

GPT-5.6 Luna is the stronger model overall, scoring 54.6 to 48.1 on the Noometry Index.

### Is GPT-5.6 Luna or Grok 4 better for coding?

GPT-5.6 Luna scores higher on coding benchmarks: 54.5 versus 50.3 in the Noometry coding category.

### How many benchmarks do GPT-5.6 Luna and Grok 4 share?

28 benchmarks have published results for both models. GPT-5.6 Luna has 52 scored results on Noometry and Grok 4 has 48.