GPT-5.5 Pro vs DeepSeek V4 Flash
30-second takeaway
- DeepSeek V4 Flash has the cheaper input: $0.39 vs $30 (per 1M tokens, 99% less)
- GPT-5.5 Pro has the larger context: 1.05M vs 1M tokens
| GPT-5.5 Pro OpenAI | DeepSeek V4 Flash AI/ML API | |
|---|---|---|
| Input | $30 | $0.39 |
| Output | $180 | $1.56 |
| Context | 1.05M | 1M |
More specs (max output / capabilities)
| max output | 128,000 | 384,000 |
| Reasoning | ✓ Yes | ✓ Yes |
| Tool calls | ✓ Yes | ✓ Yes |
| Open weights | — No | ✓ Yes |
Prices are official/data-source rates (per 1M tokens), not what relays actually charge — relay prices vary with discounts and group multipliers. See methodology.