Model comparison
o1 vs o3
OpenAI
o1
The first reasoning model - historically important, now superseded.
OpenAI
o3
OpenAI's mainstream reasoning model - production-viable thinking.
Specs
| Metric | o1 | o3 |
|---|---|---|
| Context window | 200K tokens↑ | 200K tokens |
| Input $/1M tokens | $15.00 | $2.00↑ |
| Output $/1M tokens | $60.00 | $8.00↑ |
| Modalities | Text · Image · File | Image · Text · File |
| Open weights | No | No |
| Released | Dec 2024 | Apr 2025 |
Capability differences
| Capability | o1 | o3 |
|---|---|---|
| Tool use | No | Yes |
Key differences
- -Input pricing: o1 at $15.00/1M vs o3 at $2.00/1M.