DeepSeek-V4 just launched - GPT-5 class at 1/6 the cost

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with AI That Reasons

DeepSeek delivers frontier class intelligence - open-source, affordable, and relentlessly advancing. From code to science, the future of AI is here.

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671B
Parameters (V3)
1.6T
Parameters (V4)
128K
Context Window
$0.28
Per 1M Input Tokens
MIT
Open Source License
DeepSeek-V4 1.6T Parameters — Latest
MoE Architecture 37B Active / 671B Total
Context Window 128K Tokens
DeepSeek-R1 Reasoning Champion
DeepSeek Coder 82.6% HumanEval
FP8 Training 60% Memory Reduction
Open Source MIT License
API Pricing $0.28 / 1M tokens
IMO 2025 Gold Medal
DeepSeek-V4 1.6T Parameters — Latest
MoE Architecture 37B Active / 671B Total
Context Window 128K Tokens
DeepSeek-R1 Reasoning Champion
DeepSeek Coder 82.6% HumanEval
FP8 Training 60% Memory Reduction
Open Source MIT License
API Pricing $0.28 / 1M tokens
IMO 2025 Gold Medal
Model Family

Every Model, Every Use Case

From general-purpose chat to specialized code and math reasoning — DeepSeek's open model family covers every intelligent task.

STABLE
DeepSeek-V3.2
Released Sep 2025 · Flagship Production Model

671B parameter MoE model with only 37B active per query. Introduces DeepSeek Sparse Attention (DSA) for 70% reduction in long-context inference costs. Powers deepseek-chat and deepseek-reasoner API endpoints.

671B
Parameters
128K
Context
37B
Active
🧠
REASONING
DeepSeek-R1
Released Jan 2025 · RL-trained Reasoning Model

Trained entirely via reinforcement learning — no supervised fine-tuning. Develops chain-of-thought reasoning organically. Achieves 97.3% on MATH-500 and top results on competition math, science, and logic problems.

97.3%
MATH-500
CoT
Reasoning
64K
Max Output
💻
CODE
DeepSeek-Coder V2
MoE Code Model · 340+ Languages

Purpose-built for software engineering. 82.6% on HumanEval, outperforming GPT-4o. Understands full repositories, not just snippets. Supports 340+ programming languages with strong performance on Python, Java, C++, and more.

82.6%
HumanEval
340+
Languages
2T
Code Tokens
👁️
VISION
DeepSeek-VL
Vision-Language Model · Multi-Modal

Multimodal model that understands images, charts, documents, and visual content. Process screenshots, diagrams, and photos alongside text for richer, context-aware responses.

Multi
Modal
OCR
Support
API
Ready
📐
MATH
DeepSeek-Math
Specialized Mathematics Model

Specialized in mathematical reasoning and theorem proving. Trained on extensive math datasets including competition problems (AMC, AIME, Olympiad), academic papers, and proof verification corpora.

Proof
Verification
AMC
Competition
OSS
Open Source
Access & Download

Get DeepSeek Everywhere

Access DeepSeek through a browser, download the app, integrate via API, or self-host the open-source weights on your own hardware.

🌐

Web Chat — Free

No install needed. Chat directly with DeepSeek-V3.2 and V4 in your browser. Includes DeepThink reasoning mode.

📱

Mobile App — iOS & Android

Full-featured iOS and Android apps with voice input, image upload, conversation history sync, and DeepThink mode.

⚙️

API Platform

OpenAI-compatible REST API. Switch from GPT with 2 lines of code. Pay-per-token with no monthly fees or minimums.

🐙

Self-Host (Open Source)

Download full model weights from Hugging Face or GitHub under MIT License. Run locally with sufficient GPU hardware for free — no API fees ever.

Python
Node.js
cURL
# pip install openai
from openai import OpenAI

# DeepSeek uses OpenAI-compatible API
client = OpenAI(
  api_key="<your-deepseek-api-key>",
  base_url="https://api.deepseek.com"
)

response = client.chat.completions.create(
  model="deepseek-chat", # or deepseek-reasoner
  messages=[
    {"role": "system", "content": "You are a helpful assistant."},
    {"role": "user", "content": "Explain MoE architecture"}
  ],
  stream=False
)

print(response.choices[0].message.content)
// npm install openai
import OpenAI from 'openai';

const client = new OpenAI({
  apiKey: '<your-deepseek-api-key>',
  baseURL: 'https://api.deepseek.com',
});

const completion = await client.chat.completions.create({
  model: 'deepseek-chat',
  messages: [
    { role: 'user', content: 'Hello!' }
  ],
});

console.log(completion.choices[0].message.content);
# Replace YOUR_KEY with your API key
curl https://api.deepseek.com/chat/completions \
  -H "Content-Type: application/json" \
  -H "Authorization: Bearer YOUR_KEY" \
  -d '{
    "model": "deepseek-chat",
    "messages": [
      {"role":"user","content":"Hello!"}
    ]
  }'
Use Cases

What Can You Build?

DeepSeek powers applications across every domain — from scientific research to enterprise automation and creative work.

01
Code Generation & Review

Generate, debug, refactor and review code in 340+ languages. Full repository understanding, not just snippets. Ideal for dev automation, boilerplate, and complex algorithms.

02
Scientific Research

Literature review, hypothesis generation, experiment design, and data analysis. DeepSeek-R1 handles multi-step scientific reasoning including chemistry, biology, and physics.

03
Mathematical Reasoning

Solve competition math (AMC, AIME, Olympiad), university-level problems, theorem proving, and quantitative finance. Achieved IMO 2025 Gold Medal.

04
Document Analysis

Extract, summarize and analyze PDFs, reports, legal documents and contracts. 128K context window processes entire books in a single prompt.

05
Enterprise Automation

Build intelligent agents that process emails, fill forms, route tickets and automate workflows. Tool-use and structured output for seamless integration.

06
Multilingual Content

Write, translate and localize content in 30+ languages with native-level quality. Strongest Chinese-language AI available — outperforms GPT-4o and Claude on Chinese benchmarks.

07
Education & Tutoring

Personalized step-by-step explanations in math, science, coding and languages. Adaptive to student level with patient, structured explanations and practice problems.

08
Creative Writing

Brainstorm, draft, edit and polish articles, stories, marketing copy, scripts and more. Maintain long-context narrative consistency across book-length projects.

09
Data Analysis

Interpret datasets, write analysis scripts, generate charts (via code), perform statistical analysis and summarize insights. Works with CSV, SQL, and pandas workflows.

Core Technology

Built Different. Built Better.

DeepSeek's architectural innovations set it apart from every other frontier model.

🔀
Mixture of Experts (MoE)

671B total parameters, only 37B active per token. Dramatically reduces compute cost while maintaining frontier-level intelligence. Efficient without compromise.

Multi-Token Prediction

Novel training objective that predicts multiple future tokens simultaneously — improving reasoning over long contexts and boosting sample efficiency by 3×.

🔓
Fully Open Source (MIT)

All model weights, technical reports, and training recipes published under MIT License. Self-host, fine-tune, and build commercial products freely — no restrictions.

🔬
Multi-Head Latent Attention

Novel attention mechanism that compresses the KV cache into latent vectors, reducing memory footprint up to 90% while preserving full model expressiveness.

🎯
FP8 Mixed Precision Training

First frontier model trained end-to-end in FP8 precision. Achieves 60% memory reduction and 30% faster training throughput compared to BF16 baselines.

🧩
Sparse Attention (DSA)

DeepSeek Sparse Attention reduces long-context inference complexity from O(L²) to O(kL), cutting inference costs by 70% for long documents and codebases.

🤖
Reinforcement Learning (RL)

DeepSeek-R1 trained via pure RL — no supervised fine-tuning at all. Emergent chain-of-thought reasoning, self-verification, and backtracking develop naturally.

🔧
Tool Use & Agents

Native function calling, structured JSON output, and multi-turn agent workflows. DeepSeek-V4 introduces large-scale agentic task synthesis for real-world automation.

🌐
OpenAI-Compatible API

Drop-in replacement for OpenAI's API. Change 2 lines of code — base URL and key — to migrate any existing ChatGPT integration to DeepSeek instantly.

Getting Started

How to Use DeepSeek

From zero to intelligent AI integration in minutes — whether you're a casual user or enterprise developer.

1

Choose Your Access Method

Use the free web chat, download the iOS/Android app, or sign up for an API key at platform.deepseek.com for developer access.

2

Select a Model

For general questions use deepseek-chat (V3.2). For complex math and reasoning, enable DeepThink mode or use deepseek-reasoner (R1). For code, use DeepSeek-Coder V2.

3

Write Your Prompt

Be specific. Include context, constraints, and desired output format. DeepSeek excels at structured tasks — ask for JSON, tables, step-by-step solutions, or code with explanations.

4

Use DeepThink for Hard Problems

Toggle DeepThink (R1) mode for math, coding challenges, or multi-step reasoning. The model will show its chain-of-thought before the final answer.

5

Integrate via API

Install pip install openai. Set base_url="https://api.deepseek.com" and your API key. Use models deepseek-chat or deepseek-reasoner. That's it — fully OpenAI compatible.

6

Optimize Token Usage

Use consistent system prompts to maximize cache hit rates (saves 90% on input costs). Cache hits cost $0.028/1M vs $0.28/1M for misses — a 10× difference.

DS
DeepSeek Assistant
● Online — V3.2
Can you write a Python function that checks if a number is prime?
Sure! Here's an efficient implementation:

def is_prime(n):
  if n < 2: return False
  for i in range(2, int(n**0.5)+1):
    if n % i == 0: return False
  return True

This runs in O(√n) time — much faster than checking all divisors up to n.
Now explain how it works step by step
Step-by-step breakdown:

1. Base case: Numbers < 2 (0, 1) are not prime by definition.
2. Loop to √n: If n has a factor > √n, there must be a corresponding factor < √n — so we only need to check up to √n.
3. Divisibility check: If any i divides n evenly, n is composite.
4. Return True: No divisors found → n is prime. ✅
Ask DeepSeek anything...
Pricing

Up to 95% Cheaper Than GPT-5

DeepSeek uses pay-per-token pricing with no monthly subscription required. The web chat is completely free.

Free Tier
API / Pay-As-You-Go
Self-Host
Web Chat
$0/month

Full access to DeepSeek's chat interface with no account required. Unlimited conversations with the flagship model.

DeepSeek-V3.2 (flagship model)
DeepThink (R1 reasoning mode)
Image & file uploads
Conversation history
Search the web
API access
Priority during peak hours
Start Free →
Most Popular
Mobile App
$0/month

Free iOS and Android app with all web features plus voice input, widgets, and offline conversation management.

All web features included
Voice input support
Cross-device sync
Notifications
iOS 16+ / Android 8+
API access
Download App →
API Free Credits
$5 on signup

New API accounts receive $5 in free credits — enough to process ~18M input tokens. No credit card required to start.

$5 free API credits
All models included
No card required
Full API documentation
Usage dashboard
Get API Key →
💡 No monthly fees. You only pay for tokens you use. Expense = (input tokens × input price) + (output tokens × output price). Cache hits save up to 90% on input costs.
Model Context Input (Cache Hit) Input (Cache Miss) Output Max Output
deepseek-chat (V3.2) 128K $0.028/1M $0.28/1M $0.42/1M 8K
deepseek-reasoner (R1/V3.2) 128K $0.028/1M $0.28/1M $0.42/1M 64K (CoT)
deepseek-v4-pro 128K $0.145/1M $1.74/1M $3.48/1M 65K
deepseek-v4-flash 128K $0.02/1M $0.20/1M $0.60/1M 65K
LIGHT USE / MONTH
$1–10
Personal projects
MEDIUM USE / MONTH
$10–50
Small SaaS apps
HEAVY USE / MONTH
$50–200
Production apps
Distilled / Quantized
$0/API calls

Run smaller distilled models (1.5B–70B) locally using Ollama, LM Studio, or llama.cpp. Requires 8–48GB VRAM depending on model size.

No API fees ever
Full data privacy
Works offline
Ollama / LM Studio support
Reduced capability vs full model
Get via Ollama →
Full Power
Full V3 / V4 Model
GPU infrastructure

Self-host the full 671B (V3) or 1.6T (V4) model. Requires multi-GPU server infrastructure (8×A100 for V3). Ideal for enterprises processing millions of requests.

Full model capability
MIT License — commercial OK
Complete data control
Fine-tune on your data
Requires ~$50K+ GPU infra
Hugging Face →
Cloud Providers
Cloud API

Access DeepSeek models via AWS Bedrock, Azure AI, Google Vertex AI, Together AI, Fireworks, and Groq for enterprise compliance and SLAs.

Enterprise SLAs
SOC2 / HIPAA compliance
Regional data residency
No GPU management
Higher per-token cost
AWS Bedrock →
Benchmarks & Comparison

How DeepSeek Stacks Up

Rigorous academic benchmarks comparing DeepSeek models against GPT-4o, Claude, and Gemini across coding, math, and reasoning.

● BENCHMARK SCORES (DeepSeek V3.2 vs Competitors)

DeepSeek
GPT-4o
Claude

● FULL MODEL COMPARISON TABLE

Feature DeepSeek GPT-4o Claude Gemini
Input Price /1M$0.28$2.50$3.00$1.25
Output Price /1M$0.42$10.00$15.00$5.00
Context Window128K128K200K1M
Open Source✓ MIT
Self-Hostable✓ Yes✗ No✗ No✗ No
HumanEval Score90.2%87.1%85%82%
MATH-50097.3%76.6%71.1%80%
Chain-of-Thought✓ Native✓ o-series✓ Extended✓ Deep Think
API CompatibleOpenAI APIOpenAI APIAnthropicGoogle AI
Free Web Access✓ Unlimited✓ Limited✓ Limited✓ Limited
Honest Assessment

Strengths & Limitations

DeepSeek is exceptional — but like all AI systems, it has real strengths to leverage and limitations to be aware of.

✅ Strengths

💰
Exceptional Cost Efficiency

Up to 95% cheaper than GPT-5. $0.28/1M input tokens vs $15+ for Claude Opus. Best cost-per-intelligence ratio available.

🧮
Best-in-Class Math & Coding

R1 achieved 97.3% on MATH-500, IMO 2025 Gold Medal. Coder V2 scores 82.6% on HumanEval, beating GPT-4o.

🔓
Truly Open Source

Full MIT license — self-host, fine-tune, build commercial products freely. No access restrictions or waiting lists.

🌐
Best Chinese Language AI

Outperforms GPT-4o and Claude on Chinese SimpleQA. Ideal for bilingual applications and Chinese-language content.

🔌
OpenAI API Compatible

Change 2 lines of code to migrate from ChatGPT. Zero rewriting of existing integrations.

⚠️ Limitations

🔒
Data Privacy Concerns

DeepSeek is a Chinese company. Conversations may be stored on servers in China. Not suitable for sensitive government or regulated enterprise data without self-hosting.

🌍
Censored Topics

The model avoids discussing certain sensitive political topics related to China. Content filters may restrict some responses that other models answer freely.

Slower Reasoning Mode

DeepSeek-R1's chain-of-thought is powerful but slow — each reasoning response can take 15–60 seconds. Not ideal for latency-sensitive production apps.

📈
Server Capacity During Peaks

High demand can cause rate limiting or slow responses on the free tier. Enterprises should use API credits or cloud provider deployments for reliability.

🖼️
Limited Multimodal Capability

Vision support (DeepSeek-VL) is not as mature as GPT-4V or Gemini Vision. No native audio input or image generation.

FAQ

Frequently Asked Questions

Is DeepSeek really free? +

Yes — chat.deepseek.com and the mobile apps are completely free with no usage limits for the chat interface. New API accounts also receive $5 in free credits. For high-volume API usage, you pay per token — starting at just $0.028/1M tokens with cache hits. There is no mandatory subscription plan.

What is a "token" and how much does it cost? +

A token is the smallest unit of text a model processes — roughly 0.75 words (or ~4 characters) in English. "Hello, world!" is about 4 tokens. The API charges separately for input tokens (what you send) and output tokens (what the model generates). With DeepSeek-V3.2, input tokens with cache hits cost $0.028/1M, cache misses $0.28/1M, and output tokens $0.42/1M. A typical 500-word conversation costs well under $0.01. DeepSeek also automatically caches repeated prompts (like system messages), which saves 90% on repeated inputs.

What is DeepThink / Reasoning mode? +

DeepThink (powered by DeepSeek-R1) enables chain-of-thought reasoning where the model explicitly "thinks through" a problem before answering. You can see its internal reasoning steps. It's significantly better at complex math, logic puzzles, and multi-step problems — but takes longer (15–60 seconds per response). Toggle it on in the chat interface with the "DeepThink" button, or use the deepseek-reasoner model via API. For simple questions, standard mode is faster and cheaper.

Is DeepSeek safe to use for business / sensitive data? +

For non-sensitive business use (marketing copy, code review, public data analysis), the cloud API is fine. However, DeepSeek is a Chinese company — data processed through the public API may be stored on servers subject to Chinese law. For sensitive data (healthcare, finance, legal documents), we recommend either self-hosting the open-source model weights on your own infrastructure, or using DeepSeek via compliant cloud providers (AWS Bedrock, Azure AI) that offer HIPAA/SOC2 SLAs and data residency guarantees.

How do I switch from OpenAI/ChatGPT to DeepSeek? +

DeepSeek's API is fully OpenAI-compatible. Update just two lines: set base_url="https://api.deepseek.com" and your DeepSeek api_key. Change the model name to deepseek-chat (standard) or deepseek-reasoner (reasoning). All your existing code for streaming, function calling, and structured outputs works without any other changes. Most users migrate in under 5 minutes.

Can I run DeepSeek locally on my computer? +

Yes! DeepSeek is fully open source under MIT License. For local use, the easiest method is Ollama — run ollama pull deepseek-v2 to download a quantized version. Smaller models (1.5B–7B) run on 8GB VRAM. The 67B version requires 40GB VRAM. For the full 671B V3 model, you'll need a multi-GPU server (8×A100 or equivalent). LM Studio and llama.cpp are also supported.

What is the difference between DeepSeek-V3 and DeepSeek-R1? +

DeepSeek-V3 (and V3.2) is the general-purpose flagship model — optimized for speed, versatility, and breadth. It handles chat, code, writing, and analysis efficiently. DeepSeek-R1 is a reasoning-specialized model trained via reinforcement learning to develop explicit chain-of-thought. R1 dramatically outperforms V3 on math, logic, and complex reasoning tasks, but is slower and more verbose. For everyday tasks, use V3. For hard math, science, or puzzles, use R1 (DeepThink mode).

Does DeepSeek support function calling / tool use? +

Yes. DeepSeek-V3.2 and V4 support OpenAI-compatible function calling (tool use). You can define functions in the same JSON schema format as OpenAI. DeepSeek-V4 adds a large-scale agentic task synthesis pipeline that significantly improves tool-use accuracy and generalization for building AI agents and automation workflows. Structured output (JSON mode) is also supported.

Who made DeepSeek? Is it Chinese? +

DeepSeek was founded in 2023 as a subsidiary of High-Flyer Capital Management, a prominent Chinese quantitative hedge fund. The company is headquartered in Hangzhou, China. It became globally prominent in January 2025 when DeepSeek-R1 matched GPT-4 performance while reportedly costing only ~$5.5M to train — compared to GPT-4's $100M+. The team publishes all research openly and releases model weights under MIT License.

Get Started

Ready to go deeper?

Join millions of users and developers building with frontier AI that's open, affordable, and remarkably capable.

Start Chatting Free → Get API Key GitHub ↗