# GPT-5.6 Luna vs Grok 2

> Side-by-side benchmark comparison for GPT-5.6 Luna and Grok 2 across agentic, coding, multimodal, knowledge, reasoning, multilingual, and math tasks.

- Canonical page: https://benchlm.ai/compare/gpt-5-6-luna-vs-grok-2
- Last updated: October 14, 2026

- Shared sourced benchmarks: 1
- HTML indexing: indexable
- Ranking lane: BenchAlign v5.8

## Quick Verdict

Evidence is too thin for a benchmark verdict: GPT-5.6 Luna and Grok 2 share only 1 sourced benchmark row.

## Summary

- Only 1 shared sourced benchmark row is available. That is not enough for a broad capability verdict, so this mirror does not name an overall winner.
- GPT-5.6 Luna has the larger published context window at 1.05M.

## Model Snapshot

| Property | GPT-5.6 Luna | Grok 2 |
|----------|----------|----------|
| Creator | OpenAI | xAI |
| Type | Proprietary | Proprietary |
| Reasoning | Reasoning | Non-Reasoning |
| Context | 1.05M | Unknown |
| Independent public score (not head-to-head) | 64.5 | null |
| Benchmarks Covered | 31 | 5 |
| Pricing (input/output) | $0.20 / $1.20 | N/A |

## Category Breakdown

### Agentic

- Winner: Insufficient shared evidence
- GPT-5.6 Luna public-lane score: 56.3 (Supported · #37/124)
- Grok 2 public-lane score: Coming soon

| Benchmark | GPT-5.6 Luna | Grok 2 | Winner |
|-----------|-----------|-----------|--------|
| Terminal-Bench 3.0 | 14.3% | Coming soon | Coming soon |
| Terminal-Bench 2.1 | 84.7% | Coming soon | Coming soon |
| BrowseComp | 83.3% | Coming soon | Coming soon |
| OSWorld 2.0 | 45.6% | Coming soon | Coming soon |
| CyberGym | 77.9% | Coming soon | Coming soon |
| ExploitGym | 12.4% | Coming soon | Coming soon |
| Toolathlon | 53.4% | Coming soon | Coming soon |
| Terminal-Bench 2.1 (Vals) | 79.0% | Coming soon | Coming soon |
| ApprenticeBench | 7% | Coming soon | Coming soon |

### Coding

- Winner: Insufficient shared evidence
- GPT-5.6 Luna public-lane score: 61.7 (Supported · #16/148)
- Grok 2 public-lane score: Coming soon

| Benchmark | GPT-5.6 Luna | Grok 2 | Winner |
|-----------|-----------|-----------|--------|
| SWE-bench Pro | 62.7% | Coming soon | Coming soon |
| Terminal-Bench 2.1 | 84.7% | Coming soon | Coming soon |
| DeepSWE | 67.2% | Coming soon | Coming soon |
| FrontierCode 1.1 Extended | 55.1% | Coming soon | Coming soon |
| CursorBench 3.2 | 61.1% | Coming soon | Coming soon |
| VulcanBench v3 | 85.5% | Coming soon | Coming soon |
| SWE-bench (Vals) | 93.0% | Coming soon | Coming soon |
| CursorBench 4.0 | 35.9% | Coming soon | Coming soon |
| HumanEval | Coming soon | 88.4% | Coming soon |

### Reasoning

- Winner: Insufficient shared evidence
- GPT-5.6 Luna public-lane score: 58.2 (#28/29)
- Grok 2 public-lane score: Coming soon

| Benchmark | GPT-5.6 Luna | Grok 2 | Winner |
|-----------|-----------|-----------|--------|
| ARC-AGI-2 | 59.5% | Coming soon | Coming soon |
| ARC-AGI-3 | 0.2% | Coming soon | Coming soon |
| ARC-AGI-1 | 88.00% | Coming soon | Coming soon |

### Multimodal & Grounded

- Winner: Insufficient shared evidence
- GPT-5.6 Luna public-lane score: 79.6 (#19/54)
- Grok 2 public-lane score: Coming soon

| Benchmark | GPT-5.6 Luna | Grok 2 | Winner |
|-----------|-----------|-----------|--------|
| MMMU-Pro | 78.4% | Coming soon | Coming soon |
| MMMU-Pro w/ Python | 79.5% | Coming soon | Coming soon |
| MMMU | Coming soon | 66.1% | Coming soon |

### Knowledge

- Winner: Insufficient shared evidence
- GPT-5.6 Luna public-lane score: 64.5 (Supported · #38/181)
- Grok 2 public-lane score: Coming soon

| Benchmark | GPT-5.6 Luna | Grok 2 | Winner |
|-----------|-----------|-----------|--------|
| GPQA | 92.3% | 56% | GPT-5.6 Luna |
| GPQA-D | 92.3% | Coming soon | Coming soon |
| HealthBench Professional | 55.7% | Coming soon | Coming soon |
| HealthBench Hard | 32.0% | Coming soon | Coming soon |
| GPQA Diamond (Vals) | 91.7% | Coming soon | Coming soon |
| MMLU-Pro (Vals) | 86.0% | Coming soon | Coming soon |
| MMLU | Coming soon | 87.5% | Coming soon |
| MMLU-Pro | Coming soon | 75.5% | Coming soon |

### Mathematics

- Winner: Insufficient shared evidence
- GPT-5.6 Luna public-lane score: 84 (Unranked · 3 rankable rows)
- Grok 2 public-lane score: Coming soon

| Benchmark | GPT-5.6 Luna | Grok 2 | Winner |
|-----------|-----------|-----------|--------|
| FrontierMath (legacy) | 78.6% | Coming soon | Coming soon |
| FrontierMath v2 (Tiers 1-3) | 78.600% | Coming soon | Coming soon |
| FrontierMath v2 (Tier 4) | 58.500% | Coming soon | Coming soon |

## FAQ

### Is there enough evidence to pick between GPT-5.6 Luna and Grok 2?

Not yet. The models share only 1 sourced benchmark row, so this mirror reports the available measurements and metadata without naming a broad winner.

### What can I compare safely on this page?

Published pricing, context windows, model type, and individual shared benchmark rows are directly comparable. Independent overall scores and non-overlapping benchmark coverage are labeled separately and should not be read as a controlled head-to-head result.

## Related Comparisons

- [GPT-5.6 Luna vs GPT-5.6 Sol](/compare/gpt-5-6-luna-vs-gpt-5-6-sol)
- [Grok 2 vs GPT-5.6 Sol](/compare/gpt-5-6-sol-vs-grok-2)
- [GPT-5.6 Luna vs GPT-5.6 Terra](/compare/gpt-5-6-luna-vs-gpt-5-6-terra)
- [Grok 2 vs GPT-5.6 Terra](/compare/gpt-5-6-terra-vs-grok-2)

## Explore More

- [GPT-5.6 Luna profile](/models/gpt-5-6-luna)
- [Grok 2 profile](/models/grok-2)
- [Compare Pricing](/llm-pricing)
- [Alternative Finder](/tools/alternative-finder)
- [LLM Selector](/tools/llm-selector)
- [Overall Rankings](/best/overall)