OpenAI

OpenAI: GPT-OSS 120B

Access GPT-OSS 120B 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-120b"
}).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-120b"
        }).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-120b",
    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-120b",
    "messages": [
      {"role": "user", "content": "Explain quantum computing in simple terms"}
    ]
  }'

Model Card

GPT-OSS 120B is OpenAI's most powerful open-weight model under Apache 2.0 license, achieving near-parity with o4-mini on reasoning benchmarks. It has 117B total parameters with 5.1B active, fitting on a single H100 GPU.

Context Window 131K

tokens

Max Output 131K

tokens

Input Cost $0.15

per million tokens

Output Cost $0.6

per million tokens

Release Date Jul 22, 2025

 

Output Speed 363

tokens / sec

Latency 0.52s

time to first token

Model Playground

Try GPT-OSS 120B instantly in your browser.
This playground uses the Puter.js AI API — no API keys or setup required.

Chat openai/gpt-oss-120b
OpenAI
Chat with GPT-OSS 120B
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Benchmarks

How GPT-OSS 120B performs on standard evaluations.

Artificial Analysis
Intelligence Index
33.3
Better than 74% of tracked models
Artificial Analysis
Coding Index
28.6
Better than 67% of tracked models
Artificial Analysis
Math Index
93.4
Better than 94% of tracked models
BenchmarkScore
GPQA Diamond Graduate-level science Q&A
78.2%
Humanity's Last Exam Cross-domain reasoning
18.5%
LiveCodeBench Recent coding problems
87.8%
SciCode Scientific programming
38.9%
AIME 2025 Advanced math exam
93.4%
IFBench Instruction following
69.0%
LCR Long-context reasoning
50.7%
Terminal-Bench Hard Agentic terminal tasks
23.5%
τ²-Bench Tool use / agents
65.8%

Scores sourced from Artificial Analysis.

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Frequently Asked Questions

How do I use GPT-OSS 120B?

You can access GPT-OSS 120B 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 120B free?

Yes, it is free if you're using it through Puter.js. With the User-Pays Model, you can add GPT-OSS 120B 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 120B?
GPT-OSS 120B costs $0.15 per 1M input tokens and $0.6 per 1M output tokens.
Price per 1M tokens
Input$0.15
Output$0.6
Who created GPT-OSS 120B?

GPT-OSS 120B was created by OpenAI and released on Jul 22, 2025.

What is the context window of GPT-OSS 120B?

GPT-OSS 120B 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 120B?

GPT-OSS 120B can generate up to 131K tokens in a single response.

How does GPT-OSS 120B perform on benchmarks?

GPT-OSS 120B scores 33.3 on the Artificial Analysis Intelligence Index, outperforming 74% of tracked models. On coding, it scores 28.6 (outperforms 67% of models). On math, it scores 93.4 (outperforms 94% of models).

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

Yes — the GPT-OSS 120B 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 120B to your app without worrying about API keys or setup.

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