gpt-oss-120b (free)
OpenAIReleased Aug 5, 2025Free
gpt-oss-120b is an open-weight, 117B-parameter Mixture-of-Experts (MoE) language model from OpenAI designed for high-reasoning, agentic, and general-purpose production use cases. It activates 5.1B parameters per forward pass and is optimized...
- Context window
- 131K tokens
- Max output
- 131K tokens
- Input
- text
- Output
- text
- Tokenizer
- GPT
- Knowledge cutoff
- Jun 30, 2024
- Released
- Aug 5, 2025
- Reasoning
- always on
Pricing
Per 1M tokens. The provider price and our flat 3% fee are separate columns — what you pay is their sum.
| Per 1M tokens | Provider | + 3% fee | You pay |
|---|---|---|---|
| Input | Free | — | Free |
| Output | Free | — | Free |
Benchmarks
Artificial Analysis
- Intelligence index
- 23.8
- Coding index
- 30.4
- Agentic index
- 13.2
Design Arena
| Category | Elo | Win rate | Rank |
|---|---|---|---|
| 3Dmodels | 978 | 29.4% | #90 |
| Codemodels | 1013 | 33.4% | #96 |
| Data vizmodels | 1044 | 45.1% | #86 |
| Game devmodels | 1059 | 40.6% | #84 |
| UI componentsmodels | 980 | 35.5% | #91 |
| Websitesmodels | 1011 | 32.5% | #99 |
Head-to-head preference voting. How we filter and rank
Supported parameters
- include_reasoning
- max_tokens
- min_p
- reasoning
- seed
- stop
- temperature
- tool_choice
- tools
- top_a
- top_k
- top_p
Call it
OpenAI-compatible: point your SDK at api.openkey.ai/v1 and use model openai/gpt-oss-120b:free.
curl https://api.openkey.ai/v1/chat/completions \
-H "Authorization: Bearer $OPENKEY_API_KEY" \
-H "Content-Type: application/json" \
-d '{
"model": "openai/gpt-oss-120b:free",
"messages": [{"role": "user", "content": "Hello"}]
}'import os
from openai import OpenAI
client = OpenAI(
base_url="https://api.openkey.ai/v1",
api_key=os.environ["OPENKEY_API_KEY"],
)
completion = client.chat.completions.create(
model="openai/gpt-oss-120b:free",
messages=[{"role": "user", "content": "Hello"}],
)
print(completion.choices[0].message.content)import OpenAI from "openai";
const client = new OpenAI({
baseURL: "https://api.openkey.ai/v1",
apiKey: process.env.OPENKEY_API_KEY,
});
const completion = await client.chat.completions.create({
model: "openai/gpt-oss-120b:free",
messages: [{ role: "user", content: "Hello" }],
});
console.log(completion.choices[0].message.content);Questions
- How much does gpt-oss-120b (free) cost via API?
- gpt-oss-120b (free) is free through OpenKey while OpenAI offers it at no charge. No fee applies to free models.
- What is gpt-oss-120b (free)'s context window?
- gpt-oss-120b (free) accepts up to 131K tokens of context and returns up to 131K tokens per request.
- Is gpt-oss-120b (free) OpenAI-compatible?
- Yes. Send requests to OpenKey's /v1/chat/completions endpoint with model "openai/gpt-oss-120b:free" using any OpenAI SDK — only the base URL and API key change.
- What inputs does gpt-oss-120b (free) support?
- gpt-oss-120b (free) accepts text input and produces text output. Its knowledge cutoff is Jun 30, 2024.
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