DeepSeek DeepSeek V3.1 Terminus vs xAI Grok 4 Fast — side-by-side specs.
DeepSeek DeepSeek V3.1 Terminus | xAI Grok 4 Fast | |
|---|---|---|
| Overview | ||
| Company | DeepSeek | xAI |
| Release date | Sep 22 2025 | Sep 2025 |
| Model type | — | — |
| Open source | Yes | No |
| Specifications | ||
Parameters | — | — |
Context window | — | — |
| Benchmarks | ||
| Timeline | ||
| Release gap | Grok 4 Fast shipped 21 days before DeepSeek V3.1 Terminus | |
DeepSeek V3.1 Terminus and Grok 4 Fast don't publish scores on any of the same benchmarks, so there's no direct head-to-head comparison. Grok 4 Fast shipped 21 days before DeepSeek V3.1 Terminus, so benchmark comparisons should account for the intervening progress.
DeepSeek V3.1 Terminus is an open-source / open-weight model; Grok 4 Fast is proprietary.
Direct benchmark comparisons are unavailable — DeepSeek V3.1 Terminus and Grok 4 Fast don't publish scores on any of the same benchmarks.