DeepSeek v4

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.

| PARAM | VALUE | |---|---| | base_url (OpenAI) | https://api.deepseek.com | | base_url (Anthropic) | https://api.deepseek.com/anthropic | | api_key | apply for an API key | | model* | deepseek-v4-flash deepseek-v4-pro deepseek-chat (to be deprecated on 2026/07/24)deepseek-reasoner (to be deprecated on 2026/07/24) |

• The model names deepseek-chat and deepseek-reasoner will be deprecated on 2026/07/24. For compatibility, they correspond to the non-thinking mode and thinking mode of deepseek-v4-flash, respectively.

Invoke The Chat API

Once you have obtained an API key, you can access the DeepSeek model using the following example scripts in the OpenAI API format. This is a non-stream example, you can set the stream parameter to true to get stream response.

For examples using the Anthropic API format, please refer to Anthropic 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

# Please install OpenAI SDK first: 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)

nodejs

// Please install OpenAI SDK first: npm install openai
import OpenAI from "openai";

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

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

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

main();