Upstage AI: Solar Pro 4
upstage/solar-pro-4
Access Solar Pro 4 from Upstage AI 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: "upstage/solar-pro-4"
}).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: "upstage/solar-pro-4"
}).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="upstage/solar-pro-4",
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": "upstage/solar-pro-4",
"messages": [
{"role": "user", "content": "Explain quantum computing in simple terms"}
]
}'
Model Card
Solar Pro 4 is an agentic large language model from Upstage, built for multi-step work that spans documents, terminals, and tool calls, with a 524K token context window.
Compared to Solar Pro 3, it shows large gains on agent-focused evaluations. Terminal-Bench v2.1 rose from 43.2 to 57, and AA-LCR long-document reasoning rose from 62.7 to 71. It scores 89.0 on GPQA Diamond and 81.9 on Arena-Hard v2 for Japanese.
The model supports English, Korean, and Japanese, with adjustable reasoning effort for either deep analysis or faster responses. It is designed to flag when information can't be verified rather than fabricate an answer.
Solar Pro 4 targets contract review, multi-document reconciliation, terminal-based automation, and document-heavy workflows like generating Excel, Word, and PowerPoint outputs.
Context Window 524K
tokens
Max Output 131K
tokens
Input Cost $0.03
per million tokens
Output Cost $0.12
per million tokens
Release Date Aug 10, 2026
Model Playground
Try Solar Pro 4 instantly in your browser.
This playground uses the Puter.js AI API — no API keys or setup required.
More AI Models From Upstage AI
Frequently Asked Questions
You can access Solar Pro 4 by Upstage AI 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.
Yes, it is free if you're using it through Puter.js. With the User-Pays Model, you can add Solar Pro 4 to your app at no cost — your users pay for their own AI usage directly, making it completely free for you as a developer.
| Price per 1M tokens | |
|---|---|
| Input | $0.03 |
| Output | $0.12 |
Solar Pro 4 was created by Upstage AI and released on Aug 10, 2026.
Solar Pro 4 supports a context window of 524K tokens. For reference, that is roughly equivalent to 1,049 pages of text.
Solar Pro 4 can generate up to 131K tokens in a single response.
Yes — the Solar Pro 4 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 Solar Pro 4 to your app without worrying about API keys or setup.
Read the Docs View Tutorials