What is DeepSeek? Pricing and Simple Usage Tips

DeepSeek originated in the quantitative finance sector, where High-Flyer used AI to support trading. In 2023, they spun off their AI research lab to focus on LLMs. The turning point came in January 2025 with the launch of DeepSeek-R1, which caused a global sensation: its chatbot application surpassed ChatGPT on the US App Store, leading to an 18% drop in Nvidia’s stock price due to concerns about a sharp decrease in AI development costs. DeepSeek overcame US chip restrictions by optimizing its software, using the less powerful but more efficient Nvidia H800 GPUs. To date, their models have seen a 1,000% increase in downloads on Hugging Face, with over 60,000 contributors on GitHub.

What is Deepseek?

DeepSeek is a leading artificial intelligence (AI) platform from China, specializing in developing open-source Large Language Models (LLMs) with a focus on computational efficiency and advanced reasoning capabilities. Founded in 2023 in Hangzhou by the investment fund High-Flyer Capital Management, DeepSeek has quickly become a symbol of Chinese AI innovation, challenging giants like OpenAI and Google by creating powerful models at a significantly lower cost. As of November 2025, DeepSeek is not just a company but an ecosystem that includes AI models, a chatbot, APIs, and mobile applications, with a valuation exceeding $3.4 billion and processing over 5.7 billion API calls per month.

Deepseek’s Main Models

DeepSeek stands out with its Mixture of Experts (MoE) architecture and “chain-of-thought” technique, which allows the model to activate only the necessary parts, saving resources. Below is a summary table of its notable models (data updated as of November 2025):

These models are all open-source under the MIT license, allowing for free download and customization.

1. DeepSeek-R1 (and variants like R1-0528)

Description and key features: This is an advanced reasoning model, launched in January 2025 with a major update in May 2025 (R1-0528 under the MIT license). It uses reinforcement learning (RL) directly on the base model without initial supervised fine-tuning, helping to discover natural chain-of-thought (CoT). Its performance is comparable to OpenAI o1 on math benchmarks (94.3% MATH-500), coding (CodeForces rating 1691), and general reasoning. The context length is up to 128K tokens, and it supports a “thinking mode” for complex tasks.

Applications:

• Research and problem-solving: Analyzing long documents, strategic planning, or solving math/STEM problems (e.g., used in tools like Genspark for in-depth research, increasing quality by 10% compared to closed models).
• Software development: Supporting competitive programming, debugging code, and tool-use integration (though still in development).
• Practical applications: Used in free mobile chatbots (launched on iOS/Android in January 2025) and autonomous agents like Vercel V0 (increasing coding efficiency by 33%, with 93-94% error-free code). Also applied in healthcare (analyzing clinical data) and education (personalized learning guidance).

2. DeepSeek-V3 (and variants like V3-0324, V3.1, V3.2-Exp)

Description and key features: A general-purpose model, launched in December 2024 and continuously updated: V3-0324 (March 2025) improved reasoning and tool-use; V3.1 (August 2025) incorporated a hybrid architecture (thinking/non-thinking modes), surpassing SWE-bench (coding benchmark) by 40%; V3.2-Exp (September 2025) introduced DeepSeek Sparse Attention (DSA) to optimize long context, reducing computational costs while maintaining output quality. It has a 128K context length, surpassing GPT-4.5 in math and coding. Open versions are under the MIT license.

Applications:

• Text processing and conversation: Summarization, writing, and conversation (supports web search and citations in the DeepSeek Chat interface).
• Coding and automation: Code generation, prefix completion (FIM), and function calling integration (JSON output).
• Practical applications: Used in financial reporting (accelerating data processing), education (academics/STEM), and enterprises (fine-tuning for custom agents like Fireworks RFT, reducing costs by 50%). In OCR (optical character recognition), V3.2 helps efficiently process text images, supporting translation and accessibility tools.

3. DeepSeek-Coder V2 (and new versions)

Description and key features: Specializing in coding, launched in June 2024 and updated for 2025 with MoE (Mixture of Experts) integration for increased speed. It supports long context, achieves high scores on HumanEval (coding benchmark), and is optimized for multilingual programming.

Applications:

• Software development: Code generation, debugging, and low-cost coding support (combined with Qwen for small businesses).
• Practical applications: Used in tools like Vercel or as a GitHub Copilot alternative, helping startups save costs (214x cheaper than GPT-4). Applied in blockchain (analyzing smart contracts) and process automation (automation workflows).

4. DeepSeek-VL2 (Vision-Language Model)

Description and key features: A multimodal model, launched in 2025, focusing on image-text processing with high performance and low cost. It supports vision tasks like object recognition, captioning, and integrates with LLMs for multimodal reasoning.

Applications:

• Image and video processing: Image editing, translating text within images, and video analysis.
• Practical applications: In healthcare (analyzing X-ray images), finance (processing charts), and entertainment (creating multimodal content). It is praised for its efficiency in applications that require high quality but are resource-conscious.

Comparison table of notable models

Key Features and Capabilities of Deepseek

Key Features

• Computational Efficiency: Uses techniques like Sparse Attention and visual tokens (instead of text tokens) to reduce energy consumption, allowing it to run on edge devices (under 8GB VRAM). This makes DeepSeek more environmentally friendly than American models.
• Capabilities:
  • Complex reasoning (mathematics, science, programming).
  • Multimodal: Processes images (VQA, OCR), video, and real-time data (like blockchain in crypto applications).
  • Multilingual: Supports Vietnamese, Chinese, and English; complies with censorship of sensitive content (like Tiananmen).
• Integration: Supports function calling, agentic AI (task automation), and on-device inference for small businesses.
• Applications: From writing code (DeepSeek-Coder) and data analysis to crypto assistants (like HeyElsa using DeepSeek to process $260 million in on-chain transactions).

Pros and Cons

• Pros: Free/open-source promotes the democratization of AI; high performance at a low cost; rapid innovation (from R1 to V3.2 in just 9 months).
• Cons:
  • Security: Data is sent to China, posing a risk of government control; some countries (USA, Italy, South Korea) have banned its official use due to national security concerns.
  • Performance: According to NIST evaluations (September 2025), DeepSeek underperforms GPT-5 on some US benchmarks and has content censorship.
  • Risks: Servers are sometimes overloaded; not ideal for sensitive data.

How to Use DeepSeek

DeepSeek is a powerful open-source AI platform from China, featuring models like DeepSeek-V3 (versatile, fast) and DeepSeek-R1 (specializing in logical reasoning, math, and programming). It is completely free for basic users, supports multiple languages (including Vietnamese), and can be used via the web, mobile app, or run locally. Below is a detailed step-by-step guide to get started, along with tips for optimizing performance based on official documentation and user experience.

1. Register an Account (Free and Quick)

DeepSeek requires an account for full access, but the process only takes 1-2 minutes. You can use your email, Google, or GitHub account.

Step 1: Visit the official website deepseek.com or platform.deepseek.com in your browser (supports Chrome, Firefox, Safari).

Step 2: Click the “Sign Up” button in the top right corner.

Step 3: Choose a registration method:

• Fastest: Click “Sign in with Google” to use your Google account.
• Manual: Enter your email, password, and username. (Avoid using a weak password; DeepSeek recommends enabling 2FA later).

Step 4: Check your email for a verification code and enter it in the corresponding field.

Step 5: Done! You will be redirected to the main interface. If using the mobile app, scan the QR code on the website to download it (iOS/App Store or Android/Google Play).

Note: If you encounter a server error (due to high traffic), try again in 5-10 minutes. The free account has a limit of ~50 messages/day for the R1 model, but no limit for V3.

2. Using DeepSeek via Web and Mobile App

The DeepSeek interface is simple, similar to ChatGPT but better optimized for reasoning.

On the Web (Desktop):

• Step 1: After logging in, click “New Chat” to start a new conversation.
• Step 2: Select a model from the left sidebar:
  • DeepSeek-V3 (or V3.1/V3.2): Use for writing, summarizing, and creative content – fast responses (under 5 seconds).
  • DeepSeek-R1 (or R1 Zero): Use for math, code, and logical analysis – activates “chain-of-thought” for step-by-step reasoning.
• Step 3: Enter a prompt (request) into the chat box, for example: “Explain the MoE algorithm in simple English.” Press Enter or the send button.
• Step 4: View the response. You can edit the prompt, continue the conversation, or use the “Regenerate” button to create a new version.
• Additional features: Enable “Search” to integrate web search (results from reliable sources); use “DeepThink” for R1 to make the model “think” more deeply (takes 10-30 seconds).

On the Mobile App (iOS/Android):

• Step 1: Download the app from the App Store/Google Play (search for “DeepSeek AI”).
• Step 2: Log in with your created account.
• Step 3: Select a model and chat similarly to the web version. The app supports voice input (speaking instead of typing) and dark mode.
• Step 4: Save chat history or share responses via social media.

Running Locally (Offline – For Developers):

If you want to run the model on your personal machine (no internet required, higher security):

• Download the model from Hugging Face (choose a quantized version to save RAM, e.g., for under 8GB of VRAM).
• Use a tool like LM Studio or Ollama: Install, download the .gguf file, and run the command ollama run deepseek-v3.
• Advantages: Completely free, unlimited, but requires a powerful machine (GPU recommended).

3. Using the API for Developers

DeepSeek offers a low-cost API (~$0.14 USD/1M input tokens) for integration into apps or scripts.

Step 1: After logging in, go to “API Keys” in the dashboard to create a free key (limited to 1 million tokens/month).

Step 2: Use the sample code (Python):

Python

import requests

url = “https://api.deepseek.com/v1/chat/completions”

headers = {“Authorization”: “Bearer YOUR_API_KEY”}

data = {

    “model”: “deepseek-chat”,  # Or deepseek-reasoner for R1

    “messages”: [{“role”: “user”, “content”: “Write Python code to calculate a factorial.”}],

    “max_tokens”: 1000

}

response = requests.post(url, json=data, headers=headers)

print(response.json())

• Refer to the full docs at platform.deepseek.com/docs.

Step 3: Test with a tool like Postman or integrate with Zapier for automation.

Helpful Tips for Using DeepSeek Effectively

Based on community experience (from Hugging Face, Reddit, and 2025 reviews), here are some tips to help you get the most out of it:

Deepseek Model Information

Features

Deepseek Pricing

Some additional questions about Deepseek

1. Is DeepSeek free?

Yes. All DeepSeek models are free for both research and commercial purposes. You can download the weights to run locally or use it for free via the official API.

2. How can I use DeepSeek for free?

There are 3 common ways:

• Access directly at https://chat.deepseek.com (includes DeepSeek-V3 and DeepSeek-R1)
• Use it through third-party platforms: Grok (x.com), Perplexity, You.com, Poe.com, etc.
• Download the model to run locally using Ollama, LM Studio, Llama.cpp, etc.

3. Does a DeepSeek account require a Chinese phone number?

Not anymore (as of 2025). It now fully supports registration with international emails and Google accounts.

4. Is DeepSeek censored?

Yes. As a Chinese model, DeepSeek is censored on some politically sensitive topics related to China (Taiwan, Xinjiang, Tiananmen Square…). However, the level of censorship is much lighter than ChatGPT on other topics.

5. What is DeepSeek-R1? How is it different from V3?

DeepSeek-R1 (Reasoner) is a version further trained with Reinforcement Learning, specializing in reasoning and math problem-solving. R1 often outperforms V3 on problems requiring long and complex reasoning (Math, Code, Logic).

6. Does DeepSeek support Vietnamese well?

Very well! DeepSeek-V3 and R1 are among the top models for understanding and generating Vietnamese today, second only to Qwen and some large commercial models.

7. What is the context length of DeepSeek?

• DeepSeek-V3: 128K tokens
• DeepSeek-R1: 64K tokens (a 128K version is in development)

8. Can DeepSeek be used for commercial purposes?

Absolutely. The license is MIT/Apache 2.0 (very permissive).