DeepSeek DeepSeek V3.1 Terminus vs xAI Grok 4.1 Fast — side-by-side specs.
DeepSeek DeepSeek V3.1 Terminus | xAI Grok 4.1 Fast | |
|---|---|---|
| Overview | ||
| Company | DeepSeek | xAI |
| Release date | Sep 22 2025 | Nov 19 2025 |
| Model type | — | — |
| Open source | Yes | No |
| Specifications | ||
Parameters | — | — |
Context window | — | — |
| Benchmarks | ||
Science reasoning GPQA Diamond | — | — |
Software engineering SWE-Bench Verified | — | — |
Multimodal understanding MMMU | — | — |
| Timeline | ||
| Release gap | DeepSeek V3.1 Terminus shipped 58 days before Grok 4.1 Fast | |
DeepSeek V3.1 Terminus and Grok 4.1 Fast do not have directly comparable benchmark scores published on GPQA Diamond, SWE-Bench Verified, or MMMU. DeepSeek V3.1 Terminus shipped 58 days before Grok 4.1 Fast, so benchmark comparisons should account for the intervening progress.
DeepSeek V3.1 Terminus is an open-source / open-weight model; Grok 4.1 Fast is proprietary.
Direct benchmark comparisons are unavailable — at least one of these models has not published scores on GPQA Diamond, SWE-Bench Verified, or MMMU.