OpenAI

OpenAI: GPT-OSS 20B

Access GPT-OSS 20B from OpenAI 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: "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 $0.03

per million tokens

Output Cost $0.14

per million tokens

Release Date Jul 22, 2025

 

Output Speed 254

tokens / sec

Latency 0.36s

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.

Chat openai/gpt-oss-20b
OpenAI
Chat with GPT-OSS 20B
Powered by Puter.js

Benchmarks

How GPT-OSS 20B performs on standard evaluations.

Artificial Analysis
Intelligence Index
24.5
Better than 63% of tracked models
Artificial Analysis
Coding Index
18.5
Better than 52% of tracked models
Artificial Analysis
Math Index
89.3
Better than 88% of tracked models
BenchmarkScore
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.

Frequently Asked Questions

How do I use GPT-OSS 20B?

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.

Is GPT-OSS 20B free?

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.

What is the pricing for GPT-OSS 20B?
Pricing for GPT-OSS 20B is based on the number of input and output tokens used per request.
Price per 1M tokens
Input$0.03
Output$0.14
Who created GPT-OSS 20B?

GPT-OSS 20B was created by OpenAI and released on Jul 22, 2025.

What is the context window of GPT-OSS 20B?

GPT-OSS 20B 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 GPT-OSS 20B?

GPT-OSS 20B can generate up to 131K tokens in a single response.

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

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