# GPT-5.5 Instant vs o1-mini

> GPT-5.5 Instant is the stronger model overall, scoring 42.5 to 33.7 on the Noometry Index.

- Canonical page: https://noometry.com/compare/gpt-5-5-instant-vs-o1-mini
- Last updated: 2026-10-10
- Shared benchmarks: 20

## Summary

- They share 20 benchmarks with published results for both. GPT-5.5 Instant scores higher in 7 categories and o1-mini in 1 category; 8 gaps are clear of the uncertainty.
- The widest gap is in reasoning, where GPT-5.5 Instant leads 24.2 to 8.9.
- The biggest single-benchmark swing is OTIS Mock AIME 2024-2025: 68.1% for GPT-5.5 Instant and 46.9% for o1-mini.

## Snapshot

| | GPT-5.5 Instant | o1-mini |
|---|---|---|
| Provider | OpenAI | OpenAI |
| Noometry Index | 42.5 | 33.7 |
| Rank | 99 | 230 |
| Context | — | — |
| Input $/M | — | — |
| Output $/M | — | — |
| Weights | Proprietary | Proprietary |

## Coding

- GPT-5.5 Instant: 43.7 (#73)
- o1-mini: 35.1 (#218)

| Benchmark | GPT-5.5 Instant | o1-mini |
|---|---|---|
| LMArena Coding | 1433 | 1362 |
| Aider Polyglot | — | 32.9% |
| SciCode | 48.6% | — |
| WeirdML | — | 36.3% |
| LiveBench Coding | — | 48% |
| HumanEval+ | — | 89% |
| MBPP+ | — | 78.8% |

## Agentic & Tool Use

- GPT-5.5 Instant: —
- o1-mini: 24.3 (#112)

| Benchmark | GPT-5.5 Instant | o1-mini |
|---|---|---|
| Cybench | — | 10% |

## Reasoning

- GPT-5.5 Instant: 24.2 (#149)
- o1-mini: 8.9 (#340)

| Benchmark | GPT-5.5 Instant | o1-mini |
|---|---|---|
| LMArena Hard Prompts | 1426 | 1333 |
| Epoch Capabilities Index | 142.48 | 135.82 |
| ARC-AGI-2 | — | 0.8% |
| SimpleBench | — | 18.1% |
| ARC-AGI-1 | — | 14% |
| CritPt | 0% | — |
| Chess Puzzles | 12% | — |
| LiveBench Reasoning | — | 72.3% |
| LiveBench Data Analysis | — | 57.9% |
| LiveBench | — | 57.8% |

## Math

- GPT-5.5 Instant: 26.1 (#241)
- o1-mini: 33.7 (#168)

| Benchmark | GPT-5.5 Instant | o1-mini |
|---|---|---|
| OTIS Mock AIME 2024-2025 | 68.1% | 46.9% |
| LMArena Math | 1420 | 1358 |
| FrontierMath (Tiers 1-3) | 26.3% | — |
| FrontierMath Tier 4 | 2.4% | — |
| LiveBench Math | — | 62% |
| MATH Level 5 | — | 89.2% |
| FrontierMath (Feb 2025 set) | — | 1.7% |

## Knowledge

- GPT-5.5 Instant: 48.9 (#68)
- o1-mini: 34.8 (#180)

| Benchmark | GPT-5.5 Instant | o1-mini |
|---|---|---|
| GPQA Diamond | 82.5% | 62.4% |
| LMArena Expert | 1409 | 1316 |
| Confabulations | — | 18.6% |

## Multimodal

- GPT-5.5 Instant: 39.3 (#48)
- o1-mini: —

| Benchmark | GPT-5.5 Instant | o1-mini |
|---|---|---|
| LMArena Vision | 1250 | — |
| LMArena Document | 1403 | — |

## Multilingual

- GPT-5.5 Instant: 53.0 (#76)
- o1-mini: 43.8 (#177)

| Benchmark | GPT-5.5 Instant | o1-mini |
|---|---|---|
| LMArena Non-English | 1417 | 1289 |
| LMArena Chinese | 1457 | 1314 |
| LMArena French | 1428 | 1292 |
| LMArena German | 1410 | 1278 |
| LMArena Japanese | 1408 | 1245 |
| LMArena Korean | 1393 | 1223 |
| LMArena Russian | 1430 | 1283 |
| LMArena Spanish | 1430 | 1302 |

## Instruction Following

- GPT-5.5 Instant: 74.4 (#94)
- o1-mini: 67.0 (#200)

| Benchmark | GPT-5.5 Instant | o1-mini |
|---|---|---|
| LMArena Instruction Following | 1407 | 1304 |
| LiveBench Instruction Following | — | 65.4% |

## Long Context

- GPT-5.5 Instant: 43.4 (#92)
- o1-mini: 40.1 (#156)

| Benchmark | GPT-5.5 Instant | o1-mini |
|---|---|---|
| LMArena Longer Query | 1422 | 1321 |

## Writing & Preference

- GPT-5.5 Instant: 62.0 (#81)
- o1-mini: 48.6 (#196)

| Benchmark | GPT-5.5 Instant | o1-mini |
|---|---|---|
| LMArena Text | 1419 | 1317 |
| LMArena Creative Writing | 1420 | 1244 |
| LMArena Multi-Turn | 1434 | 1314 |
| Short-Story Creative Writing | — | 64.9% |
| LiveBench Language | — | 40.9% |

## FAQ

### Is GPT-5.5 Instant better than o1-mini?

GPT-5.5 Instant is the stronger model overall, scoring 42.5 to 33.7 on the Noometry Index.

### Is GPT-5.5 Instant or o1-mini better for coding?

GPT-5.5 Instant scores higher on coding benchmarks: 43.7 versus 35.1 in the Noometry coding category.

### How many benchmarks do GPT-5.5 Instant and o1-mini share?

20 benchmarks have published results for both models. GPT-5.5 Instant has 27 scored results on Noometry and o1-mini has 39.