# GPT-5.5 Instant vs GPT-6 Sol

> GPT-6 Sol is the stronger model overall, scoring 61.8 to 42.7 on the Noometry Index.

- Canonical page: https://noometry.com/compare/gpt-5-5-instant-vs-gpt-6-sol
- Last updated: 2026-10-10
- Shared benchmarks: 25

## Summary

- They share 25 benchmarks with published results for both. GPT-5.5 Instant scores higher in 2 categories and GPT-6 Sol in 7 categories; 7 gaps are clear of the uncertainty.
- The widest gap is in math, where GPT-6 Sol leads 87.2 to 26.5.
- The biggest single-benchmark swing is FrontierMath Tier 4: 2.4% for GPT-5.5 Instant and 90% for GPT-6 Sol.

## Snapshot

| | GPT-5.5 Instant | GPT-6 Sol |
|---|---|---|
| Provider | OpenAI | OpenAI |
| Noometry Index | 42.7 | 61.8 |
| Rank | 110 | 12 |
| Context | — | 1.05M |
| Input $/M | — | $2 |
| Output $/M | — | $10 |
| Weights | Proprietary | Proprietary |

## Coding

- GPT-5.5 Instant: 44.3 (#74)
- GPT-6 Sol: 60.1 (#11)

| Benchmark | GPT-5.5 Instant | GPT-6 Sol |
|---|---|---|
| SciCode | 48.6% | 57.6% |
| LMArena Coding | 1433 | 1447 |
| DeepSWE | — | 68.8% |
| FrontierCode | — | 49.3% |
| LMArena WebDev | — | 1688 |
| ALE-Bench | — | 2,462 |

## Agentic & Tool Use

- GPT-5.5 Instant: —
- GPT-6 Sol: 37.2 (#36)

| Benchmark | GPT-5.5 Instant | GPT-6 Sol |
|---|---|---|
| APEX-Agents | — | 54.3% |
| GDP.pdf | — | 26.4% |
| Vending-Bench 2 | — | 14,428 |

## Reasoning

- GPT-5.5 Instant: 24.9 (#155)
- GPT-6 Sol: 74.0 (#9)

| Benchmark | GPT-5.5 Instant | GPT-6 Sol |
|---|---|---|
| CritPt | 0% | 30.9% |
| LMArena Hard Prompts | 1426 | 1418 |
| Epoch Capabilities Index | 142.52 | 162.72 |
| ARC-AGI-2 | — | 89.6% |
| NYT Connections (extended) | — | 90.1% |
| ARC-AGI-1 | — | 95.5% |
| Chess Puzzles | 12% | — |
| EBR-Bench | — | 53.3% |
| Mystery Game Puzzles | — | 56% |
| DTBench | — | 97.3% |
| LMCA | — | 59.1% |

## Math

- GPT-5.5 Instant: 26.5 (#259)
- GPT-6 Sol: 87.2 (#7)

| Benchmark | GPT-5.5 Instant | GPT-6 Sol |
|---|---|---|
| FrontierMath (Tiers 1-3) | 26.3% | 89.8% |
| FrontierMath Tier 4 | 2.4% | 90% |
| OTIS Mock AIME 2024-2025 | 68.1% | 100% |
| LMArena Math | 1420 | 1402 |
| ProofBench | — | 83% |

## Knowledge

- GPT-5.5 Instant: 48.9 (#74)
- GPT-6 Sol: 64.8 (#15)

| Benchmark | GPT-5.5 Instant | GPT-6 Sol |
|---|---|---|
| GPQA Diamond | 82.5% | 94.3% |
| LMArena Expert | 1409 | 1439 |
| SimpleQA Verified | — | 60.7% |
| Vectara Hallucination Rate | — | 6.5% |

## Multimodal

- GPT-5.5 Instant: 40.0 (#52)
- GPT-6 Sol: 47.6 (#10)

| Benchmark | GPT-5.5 Instant | GPT-6 Sol |
|---|---|---|
| LMArena Vision | 1250 | 1245 |
| Blueprint-Bench 2 | — | 36.9% |
| Furniture Assembly | — | 58.3% |
| LMArena Document | 1403 | — |

## Multilingual

- GPT-5.5 Instant: 52.8 (#80)
- GPT-6 Sol: 50.5 (#118)

| Benchmark | GPT-5.5 Instant | GPT-6 Sol |
|---|---|---|
| LMArena Non-English | 1417 | 1385 |
| LMArena Chinese | 1456 | 1405 |
| LMArena French | 1428 | 1410 |
| LMArena German | 1411 | 1390 |
| LMArena Japanese | 1408 | 1385 |
| LMArena Korean | 1392 | 1341 |
| LMArena Russian | 1431 | 1401 |
| LMArena Spanish | 1429 | 1384 |

## Instruction Following

- GPT-5.5 Instant: 74.2 (#100)
- GPT-6 Sol: 74.5 (#94)

| Benchmark | GPT-5.5 Instant | GPT-6 Sol |
|---|---|---|
| LMArena Instruction Following | 1406 | 1412 |

## Long Context

- GPT-5.5 Instant: 43.4 (#96)
- GPT-6 Sol: 43.1 (#108)

| Benchmark | GPT-5.5 Instant | GPT-6 Sol |
|---|---|---|
| LMArena Longer Query | 1422 | 1411 |

## Writing & Preference

- GPT-5.5 Instant: 61.8 (#85)
- GPT-6 Sol: 71.9 (#18)

| Benchmark | GPT-5.5 Instant | GPT-6 Sol |
|---|---|---|
| LMArena Text | 1419 | 1395 |
| LMArena Creative Writing | 1419 | 1378 |
| LMArena Multi-Turn | 1433 | 1412 |
| EQ-Bench Creative Writing | — | 2125 |

## FAQ

### Is GPT-5.5 Instant better than GPT-6 Sol?

GPT-6 Sol is the stronger model overall, scoring 61.8 to 42.7 on the Noometry Index.

### Is GPT-5.5 Instant or GPT-6 Sol better for coding?

GPT-6 Sol scores higher on coding benchmarks: 60.1 versus 44.3 in the Noometry coding category.

### How many benchmarks do GPT-5.5 Instant and GPT-6 Sol share?

25 benchmarks have published results for both models. GPT-5.5 Instant has 27 scored results on Noometry and GPT-6 Sol has 45.