# Aion 3.5 vs Grok 4.5

> Grok 4.5 has enough public results to be ranked (#22); Aion 3.5 does not yet, so treat this comparison as directional.

- Canonical page: https://noometry.com/compare/aion-3-5-vs-grok-4-5
- Last updated: 2026-10-10
- Shared benchmarks: 1

## Summary

- They share 1 benchmark with published results for both. Aion 3.5 scores higher in 1 category and Grok 4.5 in 0 categories; one gap is clear of the uncertainty.
- The widest gap is in writing & preference, where Aion 3.5 leads 74.9 to 65.9.
- Grok 4.5 is cheaper at $2 / $6 per million input/output tokens, against $3 / $6 for Aion 3.5.
- Grok 4.5 accepts more context: 500K tokens versus 262K.

## Snapshot

| | Aion 3.5 | Grok 4.5 |
|---|---|---|
| Provider | AionLabs | xAI |
| Noometry Index | 57.9 | 55.0 |
| Rank | — | 22 |
| Context | 262K | 500K |
| Input $/M | $3 | $2 |
| Output $/M | $6 | $6 |
| Weights | Proprietary | Proprietary |

## Coding

- Aion 3.5: —
- Grok 4.5: 51.7 (#34)

| Benchmark | Aion 3.5 | Grok 4.5 |
|---|---|---|
| DeepSWE | — | 53.8% |
| FrontierCode | — | 42.4% |
| LMArena WebDev | — | 1552 |
| SciCode | — | 54.1% |
| WeirdML | — | 46.4% |
| LMArena Coding | — | 1473 |
| ALE-Bench | — | 1,309 |

## Agentic & Tool Use

- Aion 3.5: —
- Grok 4.5: 44.4 (#15)

| Benchmark | Aion 3.5 | Grok 4.5 |
|---|---|---|
| APEX-Agents | — | 56.2% |
| τ²-bench Banking | — | 47.9% |
| PostTrainBench | — | 23.4% |
| GBAEval | — | 65.4% |
| GDP.pdf | — | 14% |
| LMArena Search | — | 1213 |
| Vending-Bench 2 | — | 3,887 |

## Reasoning

- Aion 3.5: —
- Grok 4.5: 56.0 (#23)

| Benchmark | Aion 3.5 | Grok 4.5 |
|---|---|---|
| ARC-AGI-2 | — | 52.6% |
| SimpleBench | — | 70% |
| Kagi LLM Benchmark | — | 83.5% |
| NYT Connections (extended) | — | 79.9% |
| ARC-AGI-1 | — | 87.2% |
| CritPt | — | 15.4% |
| Chess Puzzles | — | 36% |
| LMArena Hard Prompts | — | 1462 |
| DTBench | — | 96.5% |
| LMCA | — | 45.2% |
| Surface Evolver Bench | — | 74.4% |
| Epoch Capabilities Index | — | 154.02 |

## Math

- Aion 3.5: —
- Grok 4.5: 60.7 (#29)

| Benchmark | Aion 3.5 | Grok 4.5 |
|---|---|---|
| FrontierMath (Tiers 1-3) | — | 57.2% |
| FrontierMath Tier 4 | — | 24.4% |
| OTIS Mock AIME 2024-2025 | — | 97.8% |
| ProofBench | — | 31% |
| LMArena Math | — | 1457 |

## Knowledge

- Aion 3.5: —
- Grok 4.5: 62.3 (#21)

| Benchmark | Aion 3.5 | Grok 4.5 |
|---|---|---|
| GPQA Diamond | — | 93.4% |
| SimpleQA Verified | — | 48.3% |
| LMArena Expert | — | 1466 |

## Multimodal

- Aion 3.5: —
- Grok 4.5: 37.8 (#63)

| Benchmark | Aion 3.5 | Grok 4.5 |
|---|---|---|
| LMArena Vision | — | 1287 |
| Blueprint-Bench 2 | — | 27.3% |
| Furniture Assembly | — | 22.5% |
| LMArena Document | — | 1452 |

## Multilingual

- Aion 3.5: —
- Grok 4.5: 54.5 (#43)

| Benchmark | Aion 3.5 | Grok 4.5 |
|---|---|---|
| LMArena Non-English | — | 1439 |
| LMArena Chinese | — | 1497 |
| LMArena French | — | 1458 |
| LMArena German | — | 1448 |
| LMArena Japanese | — | 1425 |
| LMArena Korean | — | 1402 |
| LMArena Russian | — | 1447 |
| LMArena Spanish | — | 1452 |

## Instruction Following

- Aion 3.5: —
- Grok 4.5: 76.3 (#45)

| Benchmark | Aion 3.5 | Grok 4.5 |
|---|---|---|
| LMArena Instruction Following | — | 1446 |

## Long Context

- Aion 3.5: —
- Grok 4.5: 44.8 (#54)

| Benchmark | Aion 3.5 | Grok 4.5 |
|---|---|---|
| LMArena Longer Query | — | 1463 |

## Writing & Preference

- Aion 3.5: 74.9
- Grok 4.5: 65.9 (#40)

| Benchmark | Aion 3.5 | Grok 4.5 |
|---|---|---|
| EQ-Bench Creative Writing | 1929 | 1579 |
| LMArena Text | — | 1448 |
| LMArena Creative Writing | — | 1442 |
| LMArena Multi-Turn | — | 1457 |

## FAQ

### Is Aion 3.5 better than Grok 4.5?

Grok 4.5 has enough public results to be ranked (#22); Aion 3.5 does not yet, so treat this comparison as directional.

### Which is cheaper, Aion 3.5 or Grok 4.5?

Grok 4.5 is cheaper. It lists at $2 per million input tokens and $6 per million output tokens; Aion 3.5 lists at $3 and $6.

### Which has the bigger context window?

Grok 4.5 does, with 500K tokens against 262K.

### How many benchmarks do Aion 3.5 and Grok 4.5 share?

1 benchmark has published results for both models. Aion 3.5 has 1 scored results on Noometry and Grok 4.5 has 52.