Your First API Call

The DeepSeek API uses an API format compatible with OpenAI/Anthropic. By modifying the configuration, you can use the OpenAI/Anthropic SDK or softwares compatible with the OpenAI/Anthropic API to access the DeepSeek API.

OpenAI Base URL

https://api.deepseek.com

Anthropic Base URL

https://api.deepseek.com/anthropic

Available Models

deepseek-v4-flash

deepseek-v4-pro

deepseek-chat (deprecated)

deepseek-reasoner (deprecated)

* deepseek-chat and deepseek-reasoner will be deprecated on 2026/07/24. They correspond to the non-thinking and thinking modes of deepseek-v4-flash.

Invoke The Chat API

curl

curl https://api.deepseek.com/chat/completions \
  -H "Content-Type: application/json" \
  -H "Authorization: Bearer ${DEEPSEEK_API_KEY}" \
  -d '{
    "model": "deepseek-v4-pro",
    "messages": [
      {"role": "system", "content": "You are a helpful assistant."},
      {"role": "user", "content": "Hello!"}
    ],
    "thinking": {"type": "enabled"},
    "reasoning_effort": "high",
    "stream": false
  }'

Python

# pip3 install openai
import os
from openai import OpenAI

client = OpenAI(
    api_key=os.environ.get('DEEPSEEK_API_KEY'),
    base_url="https://api.deepseek.com"
)

response = client.chat.completions.create(
    model="deepseek-v4-pro",
    messages=[
        {"role": "system", "content": "You are a helpful assistant"},
        {"role": "user", "content": "Hello"},
    ],
    stream=False,
    reasoning_effort="high",
    extra_body={"thinking": {"type": "enabled"}}
)

print(response.choices[0].message.content)

Node.js

// npm install openai
import OpenAI from "openai";

const openai = new OpenAI({
  baseURL: 'https://api.deepseek.com',
  apiKey: process.env.DEEPSEEK_API_KEY,
});

const completion = await openai.chat.completions.create({
  model: "deepseek-v4-pro",
  messages: [
    { role: "system", content: "You are a helpful assistant." }
  ],
  thinking: {"type": "enabled"},
  reasoning_effort: "high",
  stream: false,
});

console.log(completion.choices[0].message.content);