GPT-5.5 Pro vs GPT-4o
30-second takeaway
- GPT-4o has the cheaper input: $2.5 vs $30 (per 1M tokens, 92% less)
- GPT-5.5 Pro has the larger context: 1.05M vs 128K tokens
| GPT-5.5 Pro OpenAI | GPT-4o OpenAI | |
|---|---|---|
| Input | $30 | $2.5 |
| Output | $180 | $10 |
| Context | 1.05M | 128K |
More specs (max output / capabilities)
| max output | 128,000 | 16,384 |
| Reasoning | ✓ Yes | — No |
| Tool calls | ✓ Yes | ✓ Yes |
| Open weights | — No | — No |
Prices are official/data-source rates (per 1M tokens), not what relays actually charge — relay prices vary with discounts and group multipliers. See methodology.