DeepSeek went from a niche research release to the top free app on both app stores almost overnight, and a lot of people are still figuring out what to actually do with it. How to use DeepSeek comes down to picking the right access point for your needs — web, mobile, or API — and knowing when to switch on its reasoning mode instead of relying on quick answers. Once that clicks, it’s a genuinely capable, low-cost alternative worth having alongside your other AI tools.
What Is DeepSeek?
DeepSeek is an AI lab that builds open-weight language models alongside a free consumer chatbot and a developer API. Its biggest selling point is cost and openness: the chat interface is free, the model weights are published under a permissive license, and the API pricing undercuts most major competitors by a wide margin. The current generation, DeepSeek V4, comes in two flavors — a fast general-purpose model for everyday writing and chat, and a reasoning-focused model that works through harder problems step by step before answering.
How to Use DeepSeek: Getting Started
There are three main ways to reach DeepSeek, and most people only ever need the first one.
1. Web Chat
Go to chat.deepseek.com, sign in with an email address, and start typing. No installation is required, and the free tier covers everyday use without a credit card.
2. Mobile App
DeepSeek’s official app is available for both iOS and Android, with the same core features as the web version, including chat history synced across devices.
3. Developer API
If you’re building something rather than just chatting, DeepSeek offers an API that’s compatible with common frameworks and SDK formats, making it easy to swap in as a drop-in replacement in many existing projects. This route is really only relevant if you’re a developer integrating it into an app or workflow.
Understanding Thinking Mode
The single most useful thing to learn about how to use DeepSeek well is the difference between its two response styles:
- Non-thinking mode. The model answers directly without showing its work. This is faster and cheaper, and it’s the right choice for routine writing, quick questions, and everyday tasks.
- Thinking mode. The model works through a visible chain of reasoning before giving a final answer. This is slower but noticeably more reliable for math, logic, coding problems, and anything with several dependent steps.
As a rule of thumb: if a task has one obvious right answer that requires careful multi-step logic, switch thinking mode on. For everyday writing, brainstorming, or quick lookups, leave it off and enjoy the faster responses.
A Few Things Worth Knowing Before You Rely on It
- Data handling. DeepSeek is a China-based lab, and the hosted chat and app send your data to DeepSeek’s own servers. If you handle sensitive or regulated information, it’s worth reviewing the privacy policy before using the hosted version for that kind of work.
- Self-hosting is an option. Because the model weights are open, technical users can run DeepSeek entirely on their own infrastructure, which sidesteps the hosted-data question at the cost of needing serious hardware.
- Prompt clearly, same as any AI tool. Give it context, a clear goal, and a format, and you’ll get noticeably better results than with a bare one-line question.
Frequently Asked Questions
Is DeepSeek free to use?
Yes. The web chat and mobile apps are free for everyday use. The developer API is paid, but priced well below most competing options.
Is DeepSeek safe to use with sensitive information?
Treat it with the same caution as any hosted AI chatbot, and be aware that the hosted version routes data through DeepSeek’s own servers. If privacy is a major concern, self-hosting the open-weight models is the safer route.
Do I need to know how to code to use DeepSeek?
No. The web chat and mobile app work like any other chatbot — type a question, get an answer. Coding knowledge is only needed if you want to use the developer API.
How does DeepSeek compare to ChatGPT, Claude, or Grok?
DeepSeek’s main edge is cost and openness, with strong reasoning performance for the price. For a broader comparison, see our guides on how to use ChatGPT, how to use Claude, how to use Grok, and how to use Perplexity.
Final Thoughts
Learning how to use DeepSeek well mostly comes down to two habits: pick the right access point for what you’re doing, and switch on thinking mode when a problem actually needs careful reasoning rather than a quick answer. Start with the free web chat, get comfortable with both response modes, and decide from there whether the API or self-hosting is worth exploring for your specific use case.
