GPT-5.5 vs o1
Pricing, benchmarks, and use case comparison
Quick take
- •GPT-5.5 is meaningfully stronger at speed (62 vs 30 on our capability index).
- •GPT-5.5 is 67% cheaper on input tokens, which compounds fast on high-volume or agentic workloads.
- •o1 has a 200,000 tokens (100,000 max output) context window vs 1,050,000 tokens (128,000 max output) - better for whole-repo or long-document work.
Specs comparison
| GPT-5.5 | o1 | |
|---|---|---|
| Provider | OpenAI | OpenAI |
| Type | Closed source | Closed source |
| Context window | 1,050,000 tokens (128,000 max output) | ✓200,000 tokens (100,000 max output) |
| Input / 1M tokens | ✓$5.00 | $15.00 |
| Output / 1M tokens | $30.00 | $60.00 |
| Release date | 2026-04 | 2024-12 |
Benchmarks
| Benchmark | GPT-5.5 | o1 |
|---|---|---|
| SWE-bench Verified | 82.6% | - |
| SWE-bench Pro | 58.6% | - |
| AIME 2024 | - | 74% |
| GPQA Diamond | - | 77.3% |
| Codeforces | - | ~89th percentile |
Scores sourced from official provider release posts and independent benchmark aggregators.
Which should you choose?
Choose GPT-5.5 if...
- →Complex professional coding, data analysis, and multi-tool agentic workflows
- →Long-document or large-codebase tasks needing a 1M+ context window
- →You want OpenAI's recommended default frontier model for new projects
Choose o1 if...
- →Hard, multi-step math, science, and logic problems that reward deliberate reasoning
- →Competitive programming and algorithmic problem solving
- →Existing o1-based pipelines already validated for reasoning tasks