1. Open the official service. Use the chat or app link above and complete the account steps it presents. ChinaAI does not manage DeepSeek accounts.
2. Give it one clear job. Include the relevant source text, the desired format and any constraints. For example, specify whether you want a short explanation, a table or a code fix.
3. Check the answer against the request. Verify facts, calculations and instructions separately. For code, test it before using it in a real application.

Here is a suggested starter prompt. It is a template you can adapt, not an additional test result:

Summarize the text below in three bullet points. Use only the supplied text. Keep dates and numbers unchanged. If something is unclear, say what information is missing. Text: [paste non-sensitive text here]

DeepThink and Search are separate controls. Check which are active; our four-task test used neither. For current facts, open the underlying sources and verify the answer.

Our DeepSeek Search guide shows the controls, a source-checking workflow and three first-answer tests from September 23, 2026, including one answer whose cited page did not support an extra claim.

Writing, extracting structured information, working through calculations and reviewing small pieces of code are practical starting points. We tried one example of each in the official consumer web app. The results show both useful answers and a missed instruction.

Test conditions: September 18, 2026; signed in; four English prompts with fictional data; one first response per task in a new conversation. Search was off and DeepThink was not activated. We used no attachments, regenerated answers or corrective follow-ups. The interface did not expose a precise serving-model version.

This four-task trial did not measure speed, research accuracy, image understanding or long-document performance, and cannot rank the model family.

DeepSeek advertises its official AI assistant as free. Its Google Play listing makes that claim. This does not mean unlimited capacity, guaranteed access everywhere or free API usage.

The developer API is billed by token usage. Downloadable model weights are another route: running a model yourself still requires suitable computing resources. A third-party service hosting DeepSeek can set its own prices and terms.

Use our DeepSeek pricing guide for the app/API distinction and current official API rates. If you have token counts, the cost calculator estimates their cost; it does not convert a fixed number of messages into a guaranteed bill.

DeepSeek-R1 and DeepSeek-V4.1-Flash name model releases. The assistant adds tools around models, so a feature in one API or app may be absent from another.

As of this review, the official website highlights DeepSeek-V4.1-Flash. For a developer, the actionable question is which model identifier your chosen provider accepts and what it currently serves. Our DeepSeek model guide explains current API names, the main downloadable families and the release and license checks to make before choosing one.

For downloadable releases, start with the official model repository and inspect the exact model card, license and deployment requirements. Downloadable weights do not mean every release runs on an ordinary laptop, and they do not make a hosted chat service private.

Can DeepSeek generate images? Our DeepSeek image-generation guide compares one official-chat request with four first-run images from the separate Janus-Pro demo on September 23, 2026, and explains why Vision API image input is a different task.

• Instruction compliance. Our writing test missed an explicit minimum length. Treat requirements such as format, word count and allowed sources as checks you still need to perform.
• Facts and code. A fluent explanation can contain mistakes. Verify consequential facts with reliable sources and test generated code against your actual requirements.
• Privacy of the service you choose. DeepSeek’s privacy policy describes collection of prompts, uploaded material and chat history, use of information to train models and improve its technology, and processing and storage of personal data in the People’s Republic of China. Review those terms before sharing personal or confidential material; workplace rules may also apply. Our DeepSeek safety guide helps you choose between official chat, API, third-party hosting and local use before you submit data.
• Availability and support. If the official service is unavailable, check DeepSeek’s service-status page. For a step-by-step diagnosis, use our DeepSeek troubleshooting guide. Use support in the official service for account or billing problems. ChinaAI cannot reset its accounts or manage its payments.

We have not audited DeepSeek’s security controls or tested every region. Our small consumer-app comparison does not establish that any service is suitable for sensitive work.

Can I use DeepSeek in English?

Yes. The four consumer-chat prompts in our September 18 test were in English, and DeepSeek returned English answers.

Is DeepSeek better than ChatGPT?

Our four-task comparison does not support an overall winner. Both handled the selected data, arithmetic and small code tasks correctly; their writing responses missed different parts of the brief. Read the full comparison and its limitations, then try representative examples of your own work.

Is DeepSeek open source?

DeepSeek publishes downloadable model weights and related code. Check the license of the exact release or derivative you intend to use through its official GitHub organization or model card. Model availability, hosted-service terms and the cost of running a model are separate questions.

Can I chat with DeepSeek on ChinaAI?

Live visitor chat is not active here. Our chat directory offers official service links, a question draft you can copy and clearly labelled recorded examples. Writing a draft there does not send it to an AI model. For a new live answer, open the official DeepSeek chat.