Chat Smith now gives Pro users access to DeepSeek V4 Pro, DeepSeek's most powerful open-weight model, included in the Pro plan at no extra charge.
DeepSeek V4 Pro was released on April 24, 2026 as part of the V4 series — DeepSeek's first two-tier model lineup since V3. It is a 1.6-trillion parameter Mixture-of-Experts model with 49 billion active parameters per token, a 1 million token context window, and hybrid thinking/non-thinking modes. The model is open-weight under the MIT license and scores 80.6% on SWE-bench Verified, the highest result among open-weight models.
What makes DeepSeek V4 Pro stand out
Frontier-level reasoning at open-weight cost. DeepSeek V4 Pro posts scores on agentic benchmarks that sit alongside closed proprietary models from OpenAI and Anthropic. Per output token, it is significantly cheaper than closed alternatives — making frontier-level reasoning accessible without the corresponding cost ceiling.
1 million token context window. V4 Pro supports up to 1 million tokens of context with 384K max output tokens — practical for long documents, large codebases, or multi-step agentic workflows where large amounts of context need to be held and reasoned over in a single pass.
Hybrid thinking and non-thinking modes. V4 Pro supports both extended chain-of-thought reasoning (thinking mode) and direct response mode. This lets users choose between maximum reasoning depth for complex problems and faster, lower-latency responses for straightforward tasks.
Built for software engineering and agentic tasks. The model was designed specifically for complex software engineering, advanced reasoning, and long-running agentic tasks. It supports tool calls, JSON output, and structured agentic workflows out of the box.
Included in Chat Smith Pro — no extra cost
Chat Smith Pro users can use DeepSeek V4 Pro right now without any additional subscription or credit purchase. Open the model selector, choose DeepSeek V4 Pro, and start your session. No upgrade required.
Chat Smith is built around a simple idea: give users access to the best AI tools available, all in one place, without friction.
DeepSeek V4 Pro is available now for all Chat Smith Pro users at https://chatsmith.io/model/deepseek-v4-pro.
