# GPT-6 Astra vs o3-mini

> GPT-6 Astra is the stronger model overall, scoring 70.8 to 36.7 on the Noometry Index. o3-mini costs 10× less per token, which makes it the better buy when GPT-6 Astra's lead doesn't matter for your workload.

- Canonical page: https://noometry.com/compare/gpt-6-astra-vs-o3-mini
- Last updated: 2026-10-11
- Shared benchmarks: 33

## Summary

- They share 33 benchmarks with published results for both. GPT-6 Astra scores higher in 9 categories and o3-mini in 0 categories; 9 gaps are clear of the uncertainty.
- The widest gap is in reasoning, where GPT-6 Astra leads 85.1 to 16.3.
- The biggest single-benchmark swing is FrontierMath Tier 4: 97.6% for GPT-6 Astra and 0% for o3-mini.
- o3-mini is cheaper at $1.10 / $4.40 per million input/output tokens, against $10 / $50 for GPT-6 Astra.
- GPT-6 Astra accepts more context: 1.05M tokens versus 200K.

## Snapshot

| | GPT-6 Astra | o3-mini |
|---|---|---|
| Provider | OpenAI | OpenAI |
| Noometry Index | 70.8 | 36.7 |
| Rank | 1 | 212 |
| Context | 1.05M | 200K |
| Input $/M | $10 | $1.10 |
| Output $/M | $50 | $4.40 |
| Weights | Proprietary | Proprietary |

## Coding

- GPT-6 Astra: 73.7 (#2)
- o3-mini: 40.8 (#132)

| Benchmark | GPT-6 Astra | o3-mini |
|---|---|---|
| SciCode | 56.5% | 39.8% |
| GSO | 79.4% | 1.3% |
| WeirdML | 93.6% | 43.7% |
| LMArena Coding | 1487 | 1378 |
| DeepSWE | 74.1% | — |
| FrontierCode | 53.3% | — |
| Aider Polyglot | — | 60.4% |
| LMArena WebDev | 1786 | — |
| FrontierSWE | 65.5% | — |
| LiveBench Coding | — | 82.7% |
| MirrorCode | 46.7% | — |
| CadEval | — | 54% |
| ALE-Bench | 2,951 | — |

## Agentic & Tool Use

- GPT-6 Astra: 52.9 (#3)
- o3-mini: 29.6 (#84)

| Benchmark | GPT-6 Astra | o3-mini |
|---|---|---|
| APEX-Agents | 64.7% | — |
| Remote Labor Index | 20.8% | — |
| Cybench | — | 22.5% |
| BALROG | 68.3% | — |
| GDP.pdf | 34.2% | — |
| Vending-Bench 2 | 15,515 | — |

## Reasoning

- GPT-6 Astra: 85.1 (#1)
- o3-mini: 16.3 (#305)

| Benchmark | GPT-6 Astra | o3-mini |
|---|---|---|
| ARC-AGI-2 | 95% | 3% |
| ARC-AGI-1 | 98.5% | 34.5% |
| CritPt | 31.7% | 0.3% |
| Chess Puzzles | 72% | 17% |
| LMArena Hard Prompts | 1462 | 1366 |
| Mystery Game Puzzles | 84% | 7% |
| DTBench | 97.3% | 68.8% |
| LMCA | 64.4% | 19% |
| Epoch Capabilities Index | 166.45 | 140.34 |
| SimpleBench | — | 22.8% |
| NYT Connections (extended) | 98.1% | — |
| EBR-Bench | 76.2% | — |
| LiveBench Reasoning | — | 89.6% |
| LiveBench Data Analysis | — | 70.6% |
| Bench to the Future 3 | 0.14 | — |
| ForecastBench | — | 59.6 |
| LiveBench | — | 75.9% |

## Math

- GPT-6 Astra: 93.5 (#2)
- o3-mini: 28.1 (#244)

| Benchmark | GPT-6 Astra | o3-mini |
|---|---|---|
| FrontierMath (Tiers 1-3) | 93.7% | 18.6% |
| FrontierMath Tier 4 | 97.6% | 0% |
| OTIS Mock AIME 2024-2025 | 100% | 76.9% |
| LMArena Math | 1465 | 1396 |
| ProofBench | 99% | — |
| LiveBench Math | — | 77.3% |
| MATH Level 5 | — | 96.5% |
| FrontierMath (Feb 2025 set) | — | 12.4% |
| FrontierMath Erdős | 2.9% | — |
| FrontierMath Tier 4 (v1) | — | 4.2% |

## Knowledge

- GPT-6 Astra: 75.3 (#1)
- o3-mini: 38.3 (#146)

| Benchmark | GPT-6 Astra | o3-mini |
|---|---|---|
| GPQA Diamond | 95.8% | 77% |
| SimpleQA Verified | 75.6% | 15.3% |
| LMArena Expert | 1483 | 1364 |
| Humanity's Last Exam | 54.8% | — |
| Confabulations | — | 17.9% |
| Vectara Hallucination Rate | 8.7% | — |

## Multimodal

- GPT-6 Astra: 55.0 (#3)
- o3-mini: —

| Benchmark | GPT-6 Astra | o3-mini |
|---|---|---|
| LMArena Vision | 1281 | — |
| Blueprint-Bench 2 | 49.7% | — |
| Furniture Assembly | 80% | — |
| LMArena Document | 1468 | — |

## Multilingual

- GPT-6 Astra: 53.7 (#61)
- o3-mini: 45.7 (#164)

| Benchmark | GPT-6 Astra | o3-mini |
|---|---|---|
| LMArena Non-English | 1430 | 1319 |
| LMArena Chinese | 1484 | 1379 |
| LMArena French | 1456 | 1334 |
| LMArena German | 1440 | 1303 |
| LMArena Japanese | 1379 | 1286 |
| LMArena Korean | 1426 | 1314 |
| LMArena Russian | 1436 | 1304 |
| LMArena Spanish | 1407 | 1321 |

## Instruction Following

- GPT-6 Astra: 76.3 (#44)
- o3-mini: 75.1 (#72)

| Benchmark | GPT-6 Astra | o3-mini |
|---|---|---|
| LMArena Instruction Following | 1450 | 1337 |
| LiveBench Instruction Following | — | 84.4% |

## Long Context

- GPT-6 Astra: 44.5 (#62)
- o3-mini: 33.8 (#256)

| Benchmark | GPT-6 Astra | o3-mini |
|---|---|---|
| LMArena Longer Query | 1456 | 1343 |
| Fiction.LiveBench | — | 50% |

## Writing & Preference

- GPT-6 Astra: 75.3 (#7)
- o3-mini: 50.3 (#182)

| Benchmark | GPT-6 Astra | o3-mini |
|---|---|---|
| LMArena Text | 1441 | 1337 |
| LMArena Creative Writing | 1418 | 1286 |
| LMArena Multi-Turn | 1448 | 1320 |
| Short-Story Creative Writing | — | 61.7% |
| EQ-Bench Creative Writing | 2173 | — |
| LiveBench Language | — | 50.7% |

## FAQ

### Is GPT-6 Astra better than o3-mini?

GPT-6 Astra is the stronger model overall, scoring 70.8 to 36.7 on the Noometry Index. o3-mini costs 10× less per token, which makes it the better buy when GPT-6 Astra's lead doesn't matter for your workload.

### Which is cheaper, GPT-6 Astra or o3-mini?

o3-mini is cheaper. It lists at $1.10 per million input tokens and $4.40 per million output tokens; GPT-6 Astra lists at $10 and $50.

### Is GPT-6 Astra or o3-mini better for coding?

GPT-6 Astra scores higher on coding benchmarks: 73.7 versus 40.8 in the Noometry coding category.

### Which has the bigger context window?

GPT-6 Astra does, with 1.05M tokens against 200K.

### How many benchmarks do GPT-6 Astra and o3-mini share?

33 benchmarks have published results for both models. GPT-6 Astra has 56 scored results on Noometry and o3-mini has 51.