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DeepSeek Released August 21, 2025 Synced Apr 7, 2026

DeepSeek: DeepSeek V3.1

DeepSeek-V3.1 is a large hybrid reasoning model (671B parameters, 37B active) that supports both thinking and non-thinking modes via prompt templates. It extends the DeepSeek-V3 base with a two-phase long-context...

Tool useReasoning

Why it stands out

Combines tool use with reasoning — a strong baseline for agentic and multi-step workflows.
$0.15/M input makes it practical for always-on agents, batch processing, or high-volume classification.

What to watch

Text-only input — image or audio workflows require a separate model in the pipeline.
33K context window is shorter than the longest-context frontier models available today.
No benchmark score currently tracked — evaluate using task-specific testing alongside pricing and capability data.

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Tracked events for DeepSeek: DeepSeek V3.1.

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release

DeepSeek: DeepSeek V3.1 entered the tracked catalog

August 21, 2025

DeepSeek-V3.1 is a large hybrid reasoning model (671B parameters, 37B active) that supports both thinking and non-thinking modes via prompt templates. It extends the DeepSeek-V3 base with a two-phase long-context training process, reaching up to 128K tokens, and uses FP8 microscaling for efficient inference. Users can control the reasoning behaviour with the `reasoning` `enabled` boolean. [Learn more in our docs](https://openrouter.ai/docs/use-cases/reasoning-tokens#enable-reasoning-with-default-config) The model improves tool use, code generation, and reasoning efficiency, achieving performance comparable to DeepSeek-R1 on difficult benchmarks while responding more quickly. It supports structured tool calling, code agents, and search agents, making it suitable for research, coding, and agentic workflows. It succeeds the [DeepSeek V3-0324](/deepseek/deepseek-chat-v3-0324) model and performs well on a variety of tasks.

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Recent changes

LaunchAug 21

DeepSeek launched DeepSeek: DeepSeek V3.1

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