DeepSeek-V3.1 vs GPT-5.5
Direct spec comparison of DeepSeek-V3.1 (from DeepSeek) and GPT-5.5 (from OpenAI). Want a 3- or 4-way comparison? Open the multi-model tool →
 DeepSeek-V3.1DeepSeek |  GPT-5.5OpenAI | |
|---|---|---|
| Vendor | DeepSeek | OpenAI |
| Family | DeepSeek | GPT |
| Release date | 2025-08-21 | 2026-04-23 |
| Context window | 128,000 tokens | 400,000 tokens |
| Parameters | 671B | — |
| Modality | text | text, vision, audio |
| License | MIT | proprietary |
| Source | open weights | proprietary |
| Description | Large MoE open-weight model. Predecessor to DeepSeek-V4. | OpenAI's smartest and most intuitive model — successor to GPT-5, with major coding, research, and document workflow gains. GPT-5.5 Pro variant also available for heavier reasoning. |
| Links |
More like this
Looking for a different head-to-head? Build your own comparison on the multi-model tool.
Or see all DeepSeek-V3.1 details / GPT-5.5 details.