Toggle DeepThink Mode for Advanced Problem Solving
Switch to thinking mode for complex math, coding, and logical reasoning tasks.
Utilize the `deepseek-reasoner` model name to activate the reasoning (DeepThink) mode for tasks requiring logical depth.
The Scenario
You need to solve a high-level math problem or design a complex software architecture that requires the AI to 'think' through steps rather than just predicting text.
Before & after
Solving complex math or logic puzzles required multiple prompting iterations and manual fact-checking of the AI's logic. Time cost: 15–30 minutes.
By switching the model parameter to `deepseek-reasoner`, the AI executes complex multi-step reasoning automatically. Time cost: < 1 minute.
The Prompt
Using [deepseek-reasoner], solve the following complex logic problem step-by-step: [PASTE_PROBLEM_HERE]
DeepSeek provides two distinct modes: 'deepseek-chat' for standard non-thinking conversations and 'deepseek-reasoner' for DeepThink mode, designed for high-difficulty reasoning and international competition-level coding.
Source
Change Log | DeepSeek API Docs"'deepseek-reasoner' corresponds to DeepSeek-V3.2's thinking mode... matched GPT-5 in reasoning."