DeepSeek is a free chatbot and a family of language models built by a Hangzhou start-up funded by the quant fund High-Flyer. It writes, summarises, translates, reasons step by step and codes, and stands out at maths and programming.
Its big difference is that it publishes its models with open weights (MIT licence), so anyone can run them on their own servers, and its API costs a fraction of what rivals charge. In return, the official service stores data in China and applies Chinese censorship on political topics.
It might suit you if…
Developers and companies wanting a powerful API at the lowest cost; students and curious users who want a free assistant for non-sensitive data; teams that prefer to deploy an open model on their own infrastructure.
Try a concrete use case.
If you use the API for long jobs (summarising hundreds of documents, batch translation), schedule them off-peak and pay half. For personal or company data, run the open model locally or with a European provider.
What to check.
Data from the official service is stored in China and may be used for training (opting out requires an email). The chatbot avoids or softens topics sensitive to Beijing and is under regulatory scrutiny in Europe.
Why this tier
Offers world-class mathematical reasoning and coding, 100% free in its web interface.
Pros and cons
Pros
- Free web chat and apps, no subscription.
- Open weights under the MIT licence: run it on your own server without sending anything to China.
- One of the cheapest APIs: Flash at $0.30 / $1.20 per million tokens at peak and half off-peak.
- 1M-token context and an API compatible with OpenAI and Anthropic formats.
Cons
- Sensitive privacy: data in China and no simple training toggle.
- Censorship on sensitive political topics.
- Regulatory blocks and complaints (Italy, Germany, consumer groups) and very fast model changes in the API.
Plans and pricing
| Plan | Price | What you get |
|---|---|---|
| Web chat and app | €0 | Free, no subscription; no published daily cap (can be slow at busy times). |
| API · deepseek-flash (V4.1-Flash) | $0.30 / $1.20 per million tokens (input / output, peak) | Off-peak $0.15 / $0.60; cached input from $0.003. Accepts images. |
| API · deepseek-v4-pro | $1.32 / $3.96 per million tokens (peak) | Off-peak $0.66 / $1.98. Text only. |
| API · Search / Fetch | $0.75 per 1,000 requests | DeepSeek’s own web search and fetch, billed from 1 Nov 2026. |
Official prices checked on 4 November 2026. They may vary by country, tax and billing period.
Current models
DeepSeek-V4.1-Flash (build 1017, 17 Oct 2026, with vision) and DeepSeek-V4-Pro; 1M-token context, thinking and non-thinking modes, open weights (MIT).
Where to use it
Web, iOS, Android and API; DeepSeek Harness (developer preview).
Privacy and data
Its policy (February 2026) says data is collected and stored in China and what you type may be used for training; opting out is by email and there is an EU representative. Alternative: its open models run locally or with a European provider.
Sources checked
⏱ Quick start
Get started in 5 minutes
- Go to chat.deepseek.com or install the DeepSeek app (iOS or Android).
- Sign up with your email or your Google account.
- Type your question; turn on reasoning mode for logic, maths or code problems, and web search if you need recent data.
- Ask it to show its steps and check them: it reasons well, but it can still be wrong.
- Do not enter personal or company data: under its policy it is stored in China. For that, run its open models locally or with a European provider.
Example prompts
Solve this problem step by step, explaining the reasoning for each step, and check the result at the end another way. [problem]
Write a function in [language] that [what it should do]. Include brief comments, handle edge cases and add 3 usage examples with expected output.
Write 10 multiple-choice questions on [topic] at [level] level, with the correct answer and a short explanation of why the others are wrong.
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Your rating as a member
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