DeepSeek

DeepSeek is a chat assistant made by DeepSeek, an AI research company based in Hangzhou, China. The company was set up in 2023 and is backed by the hedge fund High-Flyer. The assistant answers questions, writes text, solves maths problems and helps with code.

The app runs on the company's own models, such as DeepSeek V3 and the reasoning model DeepSeek R1. When R1 came out in January 2025, the DeepSeek mobile app rose to the top of app store charts in the United States and other countries. A thinking mode shows the model's reasoning steps before the final answer.

The web chat and the mobile apps are free to use. Developers pay per use for the DeepSeek API, which has low prices compared with many rivals. The company publishes the weights of many of its models under open licences, so other companies and researchers can run them on their own hardware. Some governments have limited its use on official devices over data concerns.