What is DeepSeek?
Quick answer
DeepSeek is a Chinese AI company that makes the DeepSeek family of large language models and a free chat app. It became widely known in early 2025 for releasing open-weight models that rivaled the best American models at a much lower cost, under the permissive MIT license.
Last updated
Updated · By Robert Breen
Why it matters for a small business
DeepSeek matters for two different reasons. Its models are strong and openly licensed: as of October 2026, its newest releases are the V4 series, including V4-Pro and V4.1-Flash, published on Hugging Face under the MIT license with context windows of up to 1 million tokens. That lets companies download and run them on their own servers, or through hosting providers, with no data going to DeepSeek.
The other reason is privacy. DeepSeek's own privacy policy says it collects, processes and stores data in the People's Republic of China, and that what you type may be used to train its models. Some governments and companies have banned the DeepSeek app on work devices for that reason. Who it suits: developers who want a capable open-weight model to host themselves. For everyday office work, most businesses should not paste client, employee or company data into the DeepSeek app or website. Check your AI acceptable use policy first.
In a real lesson: Check a Contract for Red Flags with Claude
Stepthrough has no DeepSeek lesson, and the reason is the point of this entry. The Check a contract for red flags with Claude lesson starts by telling you to "use a Claude plan your company has approved" before you upload a real contract.
Apply the same rule to any AI app. An unapproved consumer app, especially one that stores data outside your country, is the wrong place for a client's contract. A self-hosted DeepSeek model on your own server is a different decision, and one for your IT team.
Try this lesson free or read the step-by-step guide.
Common confusions
DeepSeek the app vs DeepSeek the models
The app and website send your data to DeepSeek. The open-weight models can be run by anyone, anywhere, without contacting DeepSeek at all.
Open weights vs open data
DeepSeek publishes its model weights, not its full training data. See open-weight model.
Tips
- Keep company data out of the DeepSeek app unless IT has approved it.
- If you want DeepSeek's models, use them through a host your company already trusts.
Related terms
More AI assistants terms
Where you use it: free lessons
- Check a Contract for Red Flags with Claude (Claude, 11 min)
- n8n AI Agent Tutorial: Save Social Media Ideas to Google Sheets (n8n, 12 min)
Frequently asked questions
- Is DeepSeek safe to use for work?
- The app and website store data in China and may use it for training, per DeepSeek's privacy policy. Most businesses should not use them for client or company data. Self-hosted models are a separate question for IT.
- Is DeepSeek free?
- The chat app and website are free to use. The open-weight models are free to download under the MIT license. The API is paid by tokens; check DeepSeek's pricing page.
- How do I opt out of DeepSeek training?
- DeepSeek's privacy policy says you can contact it by email to opt out, as of October 2026. There is no simple account toggle like the ones in ChatGPT or Claude.