DeepSeek V3.1 Terminus
DeepSeek · Released Sep 2025
DeepSeek V3.1 Terminus is a 671-billion-parameter mixture-of-experts language model with 37 billion activated parameters and a 131,072-token context window.
- Strengths
- Handles long documents and complex multi-turn conversations within its extended context window while maintaining the efficiency gains of sparse activation.
- Best for
- Tasks requiring substantial context retention, such as document analysis, long-form synthesis, and extended reasoning chains within a single session.
- Limitations
- Superseded by V3.2, which expanded the context window further and received performance refinements; consider V3.2 or later versions for new work.
Input / 1M
$0.27
Output / 1M
$1.00
Cached input / 1M
—
Context window
163K
Price history
Input (solid)Output (dashed)
Price change
- 30d
- in decreased 0.0% out decreased 0.0%
- 90d
- in decreased 0.0% out decreased 0.0%
- 1y
- in decreased 0.0% out increased 5.3%
- Since launch
- in decreased 0.0% out increased 5.3%
Snapshots
| Effective | Input | Output | Cached in | Note | Source |
|---|---|---|---|---|---|
| 6 Oct 2026 | $0.27 | $1.00 | — | Imported from OpenRouter | openrouter.ai |
| 5 Oct 2026 | $0.3 | $1.00 | $0.135 | Imported from OpenRouter | openrouter.ai |
| 3 Oct 2026 | $0.27 | $1.00 | — | Imported from OpenRouter | openrouter.ai |
| 29 Sep 2026 | $0.3 | $1.00 | $0.135 | Imported from OpenRouter | openrouter.ai |
| 28 Sep 2026 | $0.27 | $1.00 | — | Imported from OpenRouter | openrouter.ai |
| 20 Aug 2026 | $0.27 | $1.00 | $0.135 | Imported from OpenRouter | openrouter.ai |
| 17 Aug 2026 | $0.27 | $1.00 | — | Imported from OpenRouter | openrouter.ai |
| 12 Aug 2026 | $0.27 | $0.95 | $0.13 | Imported from OpenRouter | openrouter.ai |
| 15 Jul 2026 | $0.27 | $1.00 | $0.135 | Imported from OpenRouter | openrouter.ai |
| 11 Jun 2026 | $0.27 | $0.95 | $0.13 | Imported from OpenRouter | openrouter.ai |