# GPT-5.5 Pro vs o1

> Side-by-side benchmark comparison for GPT-5.5 Pro and o1 across agentic, coding, multimodal, knowledge, reasoning, multilingual, and math tasks.

- Canonical page: https://benchlm.ai/compare/gpt-5-5-pro-vs-o1
- Last updated: September 21, 2026

- Shared sourced benchmarks: 1
- HTML indexing: indexable
- Ranking lane: BenchAlign v5

## Quick Verdict

Evidence is too thin for a benchmark verdict: GPT-5.5 Pro and o1 share only 1 sourced benchmark row.

## Summary

- Only 1 shared sourced benchmark row is available. That is not enough for a broad capability verdict, so this mirror does not name an overall winner.
- o1 has the lower published output-token price.
- GPT-5.5 Pro has the larger published context window at 1M.

## Model Snapshot

| Property | GPT-5.5 Pro | o1 |
|----------|----------|----------|
| Creator | OpenAI | OpenAI |
| Type | Proprietary | Proprietary |
| Reasoning | Reasoning | Reasoning |
| Context | 1M | 200K |
| Independent public score (not head-to-head) | 62.2 | 46.48 |
| Benchmarks Covered | 6 | 4 |
| Pricing (input/output) | $30.00 / $180.00 | $15.00 / $60.00 |

## Category Breakdown

### Agentic

- Winner: Insufficient shared evidence
- GPT-5.5 Pro public-lane score: 59.2 (Estimated · #27/154)
- o1 public-lane score: Coming soon

| Benchmark | GPT-5.5 Pro | o1 | Winner |
|-----------|-----------|-----------|--------|
| BrowseComp | 90.1% | Coming soon | Coming soon |

### Coding

- Winner: Insufficient shared evidence
- GPT-5.5 Pro public-lane score: Coming soon
- o1 public-lane score: 44.8 (Estimated · #98/156)

### Reasoning

- Winner: Insufficient shared evidence
- GPT-5.5 Pro public-lane score: Coming soon
- o1 public-lane score: 65.7 (Unranked · 2 rankable rows)

### Knowledge

- Winner: Insufficient shared evidence
- GPT-5.5 Pro public-lane score: 59.6 (Estimated · #38/186)
- o1 public-lane score: 45.3 (Supported · #114/186)

| Benchmark | GPT-5.5 Pro | o1 | Winner |
|-----------|-----------|-----------|--------|
| HLE | 57.2% | Coming soon | Coming soon |
| HLE w/o tools | 43.1% | Coming soon | Coming soon |
| MMLU | Coming soon | 91.8% | Coming soon |
| GPQA | Coming soon | 75.7% | Coming soon |

### Instruction Following

- Winner: Insufficient shared evidence
- GPT-5.5 Pro public-lane score: Coming soon
- o1 public-lane score: 84.5 (#40/124)

| Benchmark | GPT-5.5 Pro | o1 | Winner |
|-----------|-----------|-----------|--------|
| IFEval | Coming soon | 92.2% | Coming soon |

### Mathematics

- Winner: Insufficient shared evidence
- GPT-5.5 Pro public-lane score: 70.1 (Unranked · 3 rankable rows)
- o1 public-lane score: 32.5 (Unranked · 1 rankable row)

| Benchmark | GPT-5.5 Pro | o1 | Winner |
|-----------|-----------|-----------|--------|
| FrontierMath (legacy) | 52.4% | Coming soon | Coming soon |
| FrontierMath v2 (Tiers 1-3) | 51.000% | 9.310% | GPT-5.5 Pro |
| FrontierMath v2 (Tier 4) | 39.600% | Coming soon | Coming soon |

## FAQ

### Is there enough evidence to pick between GPT-5.5 Pro and o1?

Not yet. The models share only 1 sourced benchmark row, so this mirror reports the available measurements and metadata without naming a broad winner.

### What can I compare safely on this page?

Published pricing, context windows, model type, and individual shared benchmark rows are directly comparable. Independent overall scores and non-overlapping benchmark coverage are labeled separately and should not be read as a controlled head-to-head result.

## Related Comparisons

- [GPT-5.5 Pro vs GPT-5.5](/compare/gpt-5-5-vs-gpt-5-5-pro)
- [o1 vs GPT-5.5](/compare/gpt-5-5-vs-o1)
- [GPT-5.5 Pro vs o1-preview](/compare/gpt-5-5-pro-vs-o1-preview)
- [o1 vs o1-preview](/compare/o1-vs-o1-preview)

## Explore More

- [GPT-5.5 Pro profile](/models/gpt-5-5-pro)
- [o1 profile](/models/o1)
- [Compare Pricing](/llm-pricing)
- [Alternative Finder](/tools/alternative-finder)
- [LLM Selector](/tools/llm-selector)
- [Overall Rankings](/best/overall)