// npm install @heyputer/puter.js
import { puter } from '@heyputer/puter.js';
puter.ai.chat("Explain quantum computing in simple terms", {
model: "openai/gpt-oss-20b"
}).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: "openai/gpt-oss-20b"
}).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="openai/gpt-oss-20b",
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": "openai/gpt-oss-20b",
"messages": [
{"role": "user", "content": "Explain quantum computing in simple terms"}
]
}'
Model Card
GPT-OSS 20B is OpenAI's smaller open-weight model for lower latency and local inference, matching o3-mini on common benchmarks. It requires only 16GB of memory and runs on consumer hardware.
Context Window 131K
tokens
Max Output 131K
tokens
Input Cost $0.05
per million tokens
Output Cost $0.2
per million tokens
Release Date Jul 22, 2025
Output Speed 264
tokens / sec
Latency 0.46s
time to first token
Model Playground
Try GPT-OSS 20B instantly in your browser.
This playground uses the Puter.js AI API — no API keys or setup required.
Benchmarks
How GPT-OSS 20B performs on standard evaluations.
| Benchmark | Score |
|---|---|
| GPQA Diamond Graduate-level science Q&A | 68.8% |
| Humanity's Last Exam Cross-domain reasoning | 9.8% |
| LiveCodeBench Recent coding problems | 77.7% |
| SciCode Scientific programming | 34.4% |
| AIME 2025 Advanced math exam | 89.3% |
| IFBench Instruction following | 65.1% |
| LCR Long-context reasoning | 30.7% |
| Terminal-Bench Hard Agentic terminal tasks | 10.6% |
| τ²-Bench Tool use / agents | 60.2% |
Scores sourced from Artificial Analysis.
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Frequently Asked Questions
You can access GPT-OSS 20B by OpenAI 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 GPT-OSS 20B 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 | $0.05 |
| Output | $0.2 |
GPT-OSS 20B was created by OpenAI and released on Jul 22, 2025.
GPT-OSS 20B supports a context window of 131K tokens. For reference, that is roughly equivalent to 262 pages of text.
GPT-OSS 20B can generate up to 131K tokens in a single response.
GPT-OSS 20B scores 24.5 on the Artificial Analysis Intelligence Index, outperforming 59% of tracked models. On coding, it scores 18.5 (outperforms 48% of models). On math, it scores 89.3 (outperforms 88% of models).
Yes — the GPT-OSS 20B 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 GPT-OSS 20B to your app without worrying about API keys or setup.
Read the Docs View Tutorials