o1
OpenAI
o3
OpenAI
o1 vs o3 — Full Comparison
| Metric | o1 | o3 |
|---|---|---|
| Developer | OpenAI | OpenAI |
| Released | 2024-12 | 2025-04 ✓ |
| ELO Score | 1402 | 1433 ✓ |
| MMLU | 90.8 | — |
| HumanEval | 88.1 | — |
| Context Window | 200K | 200K |
| Input Price | $15.00 | $10.00 ✓ |
| Output Price | $60.00 | $40.00 ✓ |
| Open Source | No | No |
o1
OpenAI's first reasoning model that uses chain-of-thought to solve complex math, science, and coding problems.
Full profile →o3
Advanced reasoning model succeeding o1, with significantly improved math and coding performance at reduced pricing.
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