What is DeepSeek used for?

DeepSeek is an AI company offering a chat assistant and developer API built on its DeepSeek language and reasoning models, some of which are released openly. It is a good fit for adding language-model features through an API, reasoning-heavy question answering and experimenting with openly released models.

Is DeepSeek open source?

No. DeepSeek is proprietary (closed-source) software. Open-source alternatives to DeepSeek include LibreChat, Big-AGI and Open WebUI.

What are some alternatives to DeepSeek?

DeepSeek competes with ChatGPT, Claude and Google Gemini. For open-source options, see Enlisted's ranked list of open-source DeepSeek alternatives.

DeepSeek: features, pricing and alternatives

About DeepSeek

DeepSeek is an artificial intelligence research company whose products include a chat assistant and an API platform for its language and reasoning models. Its site is primarily in Chinese with an English toggle, and it says it focuses on foundation models and releases some of them openly, including DeepSeek-V4 and DeepSeek-R1.

The chat product is available on the web and as a mobile app, with modes for deeper reasoning and for search. Developers can use the open API platform, which has its own documentation, price list and service status page, and the site also lists a desktop-oriented tool called Harness. The vendor recently announced DeepSeek-V4.1-Flash with improved text and agent performance and native image understanding.

DeepSeek's services are hosted by the company, although released model weights can be run on your own hardware under their respective licenses. It suits developers who need an API for language and reasoning models, and individuals who want a chat assistant.

Key features

Web and mobile chat assistant
Deep thinking mode for reasoning tasks
Search-assisted answers in chat
Open API platform with documentation
Openly released models such as DeepSeek-R1
Published API price list

Good fit for

→Adding language-model features through an API
→Reasoning-heavy question answering
→Experimenting with openly released models

Tags: llm; ai-chat; api; reasoning-models; open-weights; deepseek

DeepSeek: questions and answers

What is DeepSeek used for?: DeepSeek is an AI company offering a chat assistant and developer API built on its DeepSeek language and reasoning models, some of which are released openly. It is a good fit for adding language-model features through an API, reasoning-heavy question answering and experimenting with openly released models.
Is DeepSeek free?: Yes. DeepSeek has a free plan.
Is DeepSeek open source?: No. DeepSeek is proprietary (closed-source) software. Open-source alternatives to DeepSeek include LibreChat, Big-AGI and Open WebUI.
What are some alternatives to DeepSeek?: DeepSeek competes with ChatGPT, Claude and Google Gemini. For open-source options, see Enlisted's ranked list of open-source DeepSeek alternatives.