How do I use GPT-OSS 120B through YepAPI?

Sign up for a free API key, then send requests to the /v1/ai/chat endpoint.

OpenAIText Generation/v1/ai/chat

GPT-OSS 120B

Access GPT-OSS 120B through one API key. OpenAI's open-source model.

OpenAI's open-source 120B parameter model. Extremely affordable with competitive performance.

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2,400+

Developers

1.2M+

API calls served

100+

Endpoints

$0.01

Per call

Yep, that's it.

Try it live

Send a message and see GPT-OSS 120B respond in real time.

POST/v1/ai/chatopenai/gpt-oss-120b

Message *

Max Tokens

Maximum tokens in the response.

Stream

Real-time tokens

Hit "Send Request" to see the response

Context Window

131K tokens

Max Output

131K tokens

Input Price

$0.05 / 1M tokens

Output Price

$0.27 / 1M tokens

Strengths

✓

Cost-effective

At $0.05 per 1M input tokens, it is one of the cheapest capable general-purpose models available.

✓

Open source

An openly released 120B-parameter model from OpenAI, offering transparency and freedom from closed-model lock-in.

✓

General purpose

Handles a broad range of text tasks, from Q&A and summarization to drafting and reasoning, with a 131K context window.

✓

Coding

Generates and explains code across common languages, useful for scripting and developer-assistant tasks.

Quick start

Copy this snippet and start making calls with GPT-OSS 120B.

const res = await fetch('https://api.yepapi.com/v1/ai/chat', {
  method: 'POST',
  headers: {
    'x-api-key': 'YOUR_API_KEY',
    'Content-Type': 'application/json',
  },
  body: JSON.stringify({
    "model": "openai/gpt-oss-120b",
    "messages": [
      {
        "role": "user",
        "content": "Explain API gateways in 2 sentences."
      }
    ],
    "maxTokens": 256
  }),
});
const { data } = await res.json();
console.log(data.message.content);

Why use GPT-OSS 120B through YepAPI?

✓One API key for all models — no separate accounts

✓OpenAI SDK compatible — just change the base URL

✓No monthly minimums — pay per token

✓Switch models with one line of code

✓Full provider passthrough — citations, search results, and all extras included

✓Streaming and non-streaming support on every model

✓Works with Cursor, Claude, LangChain, and any LLM tool

✓Unified billing across all providers

GPT-OSS 120B API: OpenAI's open-weight 120B model

GPT-OSS 120B is OpenAI's open-weight 120-billion-parameter model, offering competitive general-purpose performance at extremely low cost with a 131K context window. YepAPI serves it through one OpenAI-compatible endpoint.

The same YepAPI key also reaches DeepSeek, Claude, Grok, Gemini, and more, plus SEO, SERP, and scraping endpoints, so this open model can slot into the same pipeline as your other tools.

What is GPT-OSS 120B?

GPT-OSS 120B is OpenAI's open-weight large language model with 120 billion parameters, released openly rather than as a closed API-only model. It provides a 131,072-token context window and up to 131,072 output tokens, and delivers competitive general-purpose performance, Q&A, summarization, drafting, reasoning, and coding, at an extremely low price. Its open-weight nature is the headline: it offers transparency and avoids lock-in to a single closed model, while still being backed by OpenAI's training. It is a strong default when you want a capable, inexpensive, openly available model for everyday text and code tasks.

Build with GPT-OSS 120B via YepAPI

Call YepAPI's OpenAI-compatible /v1/ai/chat endpoint with any OpenAI client. Set the base URL, add your key, and set the model string to GPT-OSS 120B; your existing chat-completion code works unchanged. Switching models is one string. The same key reaches the whole catalog, so you can run cheap, high-volume work on this open model and reserve premium models for the few tasks that need them, without juggling multiple integrations.

GPT-OSS 120B API pricing — $0.05 input / $0.27 output per 1M tokens

GPT-OSS 120B costs just $0.05 per 1M input tokens and $0.27 per 1M output tokens, making it one of the cheapest capable models in the catalog. At these rates you can process enormous volumes of text and code for very little, which suits batch jobs, enrichment, and developer tooling. Per-token billing keeps even heavy usage predictable and inexpensive.

GPT-OSS 120B for affordable general-purpose and coding work

GPT-OSS 120B is a strong fit for everyday assistant and developer tasks: scripting, code explanation, summarization, classification, and general Q&A at scale. Its 131K context handles long inputs, and the rock-bottom price makes it practical for high-volume agents and pipelines. For teams that value an openly released model and want to keep costs minimal without giving up broad capability, it is an easy default.

Try GPT-OSS 120B free

New YepAPI accounts get $5 in free credit with no card required. Given GPT-OSS 120B's very low prices, that credit stretches a long way, enough to run extensive tests on your real tasks, compare it against other models on the same key, and confirm fit before adding payment.