DeepSeek

DeepSeek is a Chinese AI lab whose chat app runs on its own large language models. The app works much like other general assistants: you can ask questions, work through problems step by step, write and debug code, and search the web, either in the browser or on iOS and Android.

It appeals to people who want a capable assistant at no cost, and to developers looking for an inexpensive API for reasoning and coding work. DeepSeek publishes the weights of many of its models, so they can also be run on your own hardware, but the chat app itself is a proprietary service. As the company is based in China, review its privacy terms before sharing sensitive material.

The chat app is free to use, with no paid consumer plan. The API is billed per token from a prepaid balance, with lower rates outside peak hours, so there is no fixed monthly price. DeepSeek also offers Harness, an open-source desktop agent tool currently in preview.