# GPT-5.6 Terra vs o3-pro

> GPT-5.6 Terra is the stronger model overall, scoring 59.1 to 42.7 on the Noometry Index.

- Canonical page: https://noometry.com/compare/gpt-5-6-terra-vs-o3-pro
- Last updated: 2026-10-10
- Shared benchmarks: 7

## Summary

- They share 7 benchmarks with published results for both. GPT-5.6 Terra scores higher in 4 categories and o3-pro in 1 category; 5 gaps are clear of the uncertainty.
- The widest gap is in reasoning, where GPT-5.6 Terra leads 60.6 to 24.1.
- The biggest single-benchmark swing is ARC-AGI-2: 83.9% for GPT-5.6 Terra and 4.9% for o3-pro.
- GPT-5.6 Terra is cheaper at $2 / $12 per million input/output tokens, against $20 / $80 for o3-pro.
- GPT-5.6 Terra accepts more context: 1.05M tokens versus 200K.

## Snapshot

| | GPT-5.6 Terra | o3-pro |
|---|---|---|
| Provider | OpenAI | OpenAI |
| Noometry Index | 59.1 | 42.7 |
| Rank | 15 | 94 |
| Context | 1.05M | 200K |
| Input $/M | $2 | $20 |
| Output $/M | $12 | $80 |
| Weights | Proprietary | Proprietary |

## Coding

- GPT-5.6 Terra: 57.1 (#16)
- o3-pro: 55.1 (#22)

| Benchmark | GPT-5.6 Terra | o3-pro |
|---|---|---|
| WeirdML | 78.3% | 58.2% |
| DeepSWE | 69.6% | — |
| FrontierCode | 41.3% | — |
| Aider Polyglot | — | 84.9% |
| CursorBench | 41.3% | — |
| LMArena WebDev | 1520 | — |
| SciCode | 55% | — |
| LMArena Coding | 1484 | — |
| ALE-Bench | 1,951 | — |

## Agentic & Tool Use

- GPT-5.6 Terra: 40.2 (#23)
- o3-pro: —

| Benchmark | GPT-5.6 Terra | o3-pro |
|---|---|---|
| APEX-Agents | 58.2% | — |
| BALROG | 53.2% | — |
| GDP.pdf | 24.7% | — |
| Vending-Bench 2 | 7,343 | — |

## Reasoning

- GPT-5.6 Terra: 60.6 (#19)
- o3-pro: 24.1 (#152)

| Benchmark | GPT-5.6 Terra | o3-pro |
|---|---|---|
| ARC-AGI-2 | 83.9% | 4.9% |
| Kagi LLM Benchmark | 51.3% | 72.1% |
| ARC-AGI-1 | 96.5% | 59.3% |
| DTBench | 93.3% | 86.9% |
| LMCA | 55% | 38.5% |
| Epoch Capabilities Index | 159.31 | 147.43 |
| SimpleBench | 48.9% | — |
| NYT Connections (extended) | 78.4% | — |
| CritPt | 30% | — |
| Chess Puzzles | 54% | — |
| LMArena Hard Prompts | 1467 | — |
| Mystery Game Puzzles | 35% | — |
| Surface Evolver Bench | 83.8% | — |

## Math

- GPT-5.6 Terra: 81.5 (#10)
- o3-pro: —

| Benchmark | GPT-5.6 Terra | o3-pro |
|---|---|---|
| FrontierMath (Tiers 1-3) | 86% | — |
| FrontierMath Tier 4 | 70.7% | — |
| OTIS Mock AIME 2024-2025 | 99.7% | — |
| ProofBench | 74% | — |
| LMArena Math | 1463 | — |

## Knowledge

- GPT-5.6 Terra: 61.3 (#27)
- o3-pro: 29.0 (#234)

| Benchmark | GPT-5.6 Terra | o3-pro |
|---|---|---|
| GPQA Diamond | 93.3% | — |
| SimpleQA Verified | 43.2% | — |
| Confabulations | — | 14.2% |
| Vectara Hallucination Rate | — | 23.3% |
| LMArena Expert | 1492 | — |

## Multimodal

- GPT-5.6 Terra: 47.5 (#10)
- o3-pro: —

| Benchmark | GPT-5.6 Terra | o3-pro |
|---|---|---|
| LMArena Vision | 1271 | — |
| Blueprint-Bench 2 | 30.8% | — |
| Furniture Assembly | 54.2% | — |
| LMArena Document | 1472 | — |

## Multilingual

- GPT-5.6 Terra: 54.5 (#42)
- o3-pro: —

| Benchmark | GPT-5.6 Terra | o3-pro |
|---|---|---|
| LMArena Non-English | 1439 | — |
| LMArena Chinese | 1514 | — |
| LMArena French | 1476 | — |
| LMArena German | 1462 | — |
| LMArena Japanese | 1446 | — |
| LMArena Korean | 1420 | — |
| LMArena Russian | 1450 | — |
| LMArena Spanish | 1455 | — |

## Instruction Following

- GPT-5.6 Terra: 76.6 (#38)
- o3-pro: —

| Benchmark | GPT-5.6 Terra | o3-pro |
|---|---|---|
| LMArena Instruction Following | 1453 | — |

## Long Context

- GPT-5.6 Terra: 44.4 (#64)
- o3-pro: 72.1 (#1)

| Benchmark | GPT-5.6 Terra | o3-pro |
|---|---|---|
| Fiction.LiveBench | — | 97.2% |
| LMArena Longer Query | 1452 | — |

## Writing & Preference

- GPT-5.6 Terra: 70.4 (#21)
- o3-pro: 57.1 (#128)

| Benchmark | GPT-5.6 Terra | o3-pro |
|---|---|---|
| LMArena Text | 1446 | — |
| LMArena Creative Writing | 1411 | — |
| Short-Story Creative Writing | — | 84.4% |
| EQ-Bench Creative Writing | 1855 | — |
| EQ-Bench 4 | 1234 | — |
| LMArena Multi-Turn | 1451 | — |

## FAQ

### Is GPT-5.6 Terra better than o3-pro?

GPT-5.6 Terra is the stronger model overall, scoring 59.1 to 42.7 on the Noometry Index.

### Which is cheaper, GPT-5.6 Terra or o3-pro?

GPT-5.6 Terra is cheaper. It lists at $2 per million input tokens and $12 per million output tokens; o3-pro lists at $20 and $80.

### Is GPT-5.6 Terra or o3-pro better for coding?

GPT-5.6 Terra scores higher on coding benchmarks: 57.1 versus 55.1 in the Noometry coding category.

### Which has the bigger context window?

GPT-5.6 Terra does, with 1.05M tokens against 200K.

### How many benchmarks do GPT-5.6 Terra and o3-pro share?

7 benchmarks have published results for both models. GPT-5.6 Terra has 52 scored results on Noometry and o3-pro has 12.