# Aion 3.5 vs Claude Opus 4.8

> Claude Opus 4.8 has enough public results to be ranked (#13); Aion 3.5 does not yet, so treat this comparison as directional.

- Canonical page: https://noometry.com/compare/aion-3-5-vs-claude-opus-4-8
- Last updated: 2026-10-12
- Shared benchmarks: 1

## Summary

- They share 1 benchmark with published results for both. Aion 3.5 scores higher in 1 category and Claude Opus 4.8 in 0 categories; one gap is clear of the uncertainty.
- Aion 3.5 is cheaper at $3 / $6 per million input/output tokens, against $5 / $25 for Claude Opus 4.8.
- Claude Opus 4.8 accepts more context: 1M tokens versus 262K.

## Snapshot

| | Aion 3.5 | Claude Opus 4.8 |
|---|---|---|
| Provider | AionLabs | Anthropic |
| Noometry Index | 58.1 | 60.7 |
| Rank | — | 13 |
| Context | 262K | 1M |
| Input $/M | $3 | $5 |
| Output $/M | $6 | $25 |
| Weights | Proprietary | Proprietary |

## Coding

- Aion 3.5: —
- Claude Opus 4.8: 59.9 (#12)

| Benchmark | Aion 3.5 | Claude Opus 4.8 |
|---|---|---|
| DeepSWE | — | 59% |
| FrontierCode | — | 46.5% |
| LMArena WebDev | — | 1556 |
| SciCode | — | 53.5% |
| GSO | — | 47.1% |
| WeirdML | — | 82.9% |
| LMArena Coding | — | 1490 |
| ALE-Bench | — | 1,564 |

## Agentic & Tool Use

- Aion 3.5: —
- Claude Opus 4.8: 47.6 (#11)

| Benchmark | Aion 3.5 | Claude Opus 4.8 |
|---|---|---|
| APEX-Agents | — | 48.9% |
| OSWorld 2.0 | — | 20.6% |
| Remote Labor Index | — | 8.3% |
| τ²-bench Banking | — | 39.7% |
| DeepResearch Bench | — | 50.2% |
| PostTrainBench | — | 33.8% |
| GBAEval | — | 70.9% |
| GDP.pdf | — | 24% |
| LMArena Search | — | 1204 |
| Vending-Bench 2 | — | 5,787 |

## Reasoning

- Aion 3.5: —
- Claude Opus 4.8: 64.7 (#16)

| Benchmark | Aion 3.5 | Claude Opus 4.8 |
|---|---|---|
| ARC-AGI-2 | — | 72.1% |
| SimpleBench | — | 64.8% |
| Kagi LLM Benchmark | — | 88.8% |
| NYT Connections (extended) | — | 91.1% |
| ARC-AGI-1 | — | 92.5% |
| CritPt | — | 20.9% |
| Chess Puzzles | — | 34% |
| EnigmaEval | — | 23.5% |
| EBR-Bench | — | 28.6% |
| LMArena Hard Prompts | — | 1482 |
| Mystery Game Puzzles | — | 36% |
| DTBench | — | 94.9% |
| LMCA | — | 57.5% |
| Surface Evolver Bench | — | 87.5% |
| Bench to the Future 3 | — | 0.14 |
| Epoch Capabilities Index | — | 158.21 |
| ForecastBench | — | 59.9 |

## Math

- Aion 3.5: —
- Claude Opus 4.8: 78.4 (#13)

| Benchmark | Aion 3.5 | Claude Opus 4.8 |
|---|---|---|
| FrontierMath (Tiers 1-3) | — | 80% |
| FrontierMath Tier 4 | — | 56.1% |
| MathArena Final-Answer Competitions | — | 91.8% |
| OTIS Mock AIME 2024-2025 | — | 98.3% |
| ProofBench | — | 69% |
| LMArena Math | — | 1487 |
| FrontierMath (Feb 2025 set) | — | 47.2% |
| FrontierMath Tier 4 (v1) | — | 31.3% |

## Knowledge

- Aion 3.5: —
- Claude Opus 4.8: 61.3 (#29)

| Benchmark | Aion 3.5 | Claude Opus 4.8 |
|---|---|---|
| GPQA Diamond | — | 91% |
| SimpleQA Verified | — | 53% |
| LMArena Expert | — | 1502 |

## Multimodal

- Aion 3.5: —
- Claude Opus 4.8: 42.9 (#26)

| Benchmark | Aion 3.5 | Claude Opus 4.8 |
|---|---|---|
| LMArena Vision | — | 1294 |
| Blueprint-Bench 2 | — | 14.5% |
| Furniture Assembly | — | 42.5% |
| LMArena Document | — | 1475 |

## Multilingual

- Aion 3.5: —
- Claude Opus 4.8: 55.2 (#33)

| Benchmark | Aion 3.5 | Claude Opus 4.8 |
|---|---|---|
| LMArena Non-English | — | 1450 |
| LMArena Chinese | — | 1507 |
| LMArena French | — | 1481 |
| LMArena German | — | 1472 |
| LMArena Japanese | — | 1440 |
| LMArena Korean | — | 1432 |
| LMArena Russian | — | 1474 |
| LMArena Spanish | — | 1466 |

## Instruction Following

- Aion 3.5: —
- Claude Opus 4.8: 77.4 (#24)

| Benchmark | Aion 3.5 | Claude Opus 4.8 |
|---|---|---|
| LMArena Instruction Following | — | 1476 |

## Long Context

- Aion 3.5: —
- Claude Opus 4.8: 45.4 (#35)

| Benchmark | Aion 3.5 | Claude Opus 4.8 |
|---|---|---|
| LMArena Longer Query | — | 1483 |

## Writing & Preference

- Aion 3.5: 74.9
- Claude Opus 4.8: 72.0 (#16)

| Benchmark | Aion 3.5 | Claude Opus 4.8 |
|---|---|---|
| EQ-Bench Creative Writing | 1929 | 1840 |
| LMArena Text | — | 1461 |
| LMArena Creative Writing | — | 1454 |
| EQ-Bench 4 | — | 1281 |
| LMArena Multi-Turn | — | 1476 |

## FAQ

### Is Aion 3.5 better than Claude Opus 4.8?

Claude Opus 4.8 has enough public results to be ranked (#13); Aion 3.5 does not yet, so treat this comparison as directional.

### Which is cheaper, Aion 3.5 or Claude Opus 4.8?

Aion 3.5 is cheaper. It lists at $3 per million input tokens and $6 per million output tokens; Claude Opus 4.8 lists at $5 and $25.

### Which has the bigger context window?

Claude Opus 4.8 does, with 1M tokens against 262K.

### How many benchmarks do Aion 3.5 and Claude Opus 4.8 share?

1 benchmark has published results for both models. Aion 3.5 has 1 scored results on Noometry and Claude Opus 4.8 has 65.