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Baidu: ERNIE 4.5 21B A3B Thinking

baidu/ernie-4.5-21b-a3b-thinking

Access ERNIE 4.5 21B A3B Thinking from Baidu using Puter.js AI API.

Get Started 
// npm install @heyputer/puter.js
import { puter } from '@heyputer/puter.js';

puter.ai.chat("Explain quantum computing in simple terms", {
    model: "baidu/ernie-4.5-21b-a3b-thinking"
}).then(response => {
    document.body.innerHTML = response.message.content;
});

<html>
<body>
    <script src="https://js.puter.com/v2/"></script>
    <script>
        puter.ai.chat("Explain quantum computing in simple terms", {
            model: "baidu/ernie-4.5-21b-a3b-thinking"
        }).then(response => {
            document.body.innerHTML = response.message.content;
        });
    </script>
</body>
</html>

# pip install openai
from openai import OpenAI

client = OpenAI(
    base_url="https://api.puter.com/puterai/openai/v1/",
    api_key="YOUR_PUTER_AUTH_TOKEN",
)

response = client.chat.completions.create(
    model="baidu/ernie-4.5-21b-a3b-thinking",
    messages=[
        {"role": "user", "content": "Explain quantum computing in simple terms"}
    ],
)

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

curl https://api.puter.com/puterai/openai/v1/chat/completions \
  -H "Content-Type: application/json" \
  -H "Authorization: Bearer YOUR_PUTER_AUTH_TOKEN" \
  -d '{
    "model": "baidu/ernie-4.5-21b-a3b-thinking",
    "messages": [
      {"role": "user", "content": "Explain quantum computing in simple terms"}
    ]
  }'

Model Card

ERNIE 4.5 21B A3B Thinking is Baidu's reasoning-enhanced language model built on the 21B A3B architecture with explicit chain-of-thought capabilities. It activates only 3B of its 21B parameters per token while specializing in logic, mathematics, coding, and multi-step reasoning tasks. The model supports extended context up to 131K tokens and is optimized for complex problem-solving through structured thinking.

Context Window 131K

tokens

Max Output 66K

tokens

Input Cost $0.07

per million tokens

Output Cost $0.28

per million tokens

Release Date Jun 30, 2025

 

Model Playground

Try ERNIE 4.5 21B A3B Thinking instantly in your browser.
This playground uses the Puter.js AI API — no API keys or setup required.

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ERNIE 4.5 VL 28B A3B is a lightweight multimodal vision-language model with 28B total parameters but only 3B active per token. It processes both images and text simultaneously, enabling tasks like image comprehension, chart analysis, document understanding, and cross-modal reasoning. The model offers both thinking and non-thinking modes while matching performance of larger models like Qwen2.5-VL-32B.

Frequently Asked Questions

How do I use ERNIE 4.5 21B A3B Thinking?

You can access ERNIE 4.5 21B A3B Thinking by Baidu through Puter.js AI API. Include the library in your web app or Node.js project and start making calls with just a few lines of JavaScript — no backend and no configuration required. You can also use it with Python or cURL via Puter's OpenAI-compatible API.

Is ERNIE 4.5 21B A3B Thinking free?

Yes, it is free if you're using it through Puter.js. With the User-Pays Model, you can add ERNIE 4.5 21B A3B Thinking to your app at no cost — your users pay for their own AI usage directly, making it completely free for you as a developer.

What is the pricing for ERNIE 4.5 21B A3B Thinking?
Pricing for ERNIE 4.5 21B A3B Thinking is based on the number of input and output tokens used per request.
Price per 1M tokens
Input$0.07
Output$0.28
Who created ERNIE 4.5 21B A3B Thinking?

ERNIE 4.5 21B A3B Thinking was created by Baidu and released on Jun 30, 2025.

What is the context window of ERNIE 4.5 21B A3B Thinking?

ERNIE 4.5 21B A3B Thinking supports a context window of 131K tokens. For reference, that is roughly equivalent to 262 pages of text.

What is the max output length of ERNIE 4.5 21B A3B Thinking?

ERNIE 4.5 21B A3B Thinking can generate up to 66K tokens in a single response.

Does it work with React / Vue / Vanilla JS / Node / etc.?

Yes — the ERNIE 4.5 21B A3B Thinking API works with any JavaScript framework, Node.js, or plain HTML through Puter.js. Just include the library and start building. See the documentation for more details.

Get started with Puter.js

Add ERNIE 4.5 21B A3B Thinking to your app without worrying about API keys or setup.

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