Using gpt-oss-120b on Featherless

Implementation guide · GPT-OSS · OpenAI

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Featherless exposes gpt-oss-120b through model ID openai/gpt-oss-120b. Use the setup steps, sourced pricing, capabilities, and official provider links below to validate this route before deployment.

Last refreshed 2026-09-24. Next refresh: weekly.

Quick Start

1
Create an account at Featherless and generate an API key.
2
Use the Featherless SDK or REST API to call openai/gpt-oss-120b — see the documentation for request format.
3
You'll be billed $0.15/1M input, $0.60/1M output tokens. See full pricing.

API Portal Documentation Pricing Model Card

Code Examples

Install

pip install openai

API key

FEATHERLESS_API_KEY

Model ID

openai/gpt-oss-120b

Use exact Featherless catalog id in modelProvider.providerModelId (HF-style org/name). Not interchangeable with LLM Reference slugs.

import os
from openai import OpenAI

client = OpenAI(
    base_url="https://api.featherless.ai/v1",
    api_key=os.environ["FEATHERLESS_API_KEY"],
)
response = client.chat.completions.create(
    model="openai/gpt-oss-120b",
    messages=[{"role": "user", "content": "Hello!"}],
)
print(response.choices[0].message.content)

Pricing on Featherless

Type	Price (per 1M)
Input tokens	$0.15
Output tokens	$0.60

Capabilities

JSON / Tool useStructured Outputs

About gpt-oss-120b

OpenAI open-weight model with 120 billion parameters. Text-only model supporting reasoning, function calling, and structured outputs. Free for self-hosting. Released August 5, 2025.

Full model details →

Model Specs

Released2025-08-05

Parameters120B

Context131k

ArchitectureDecoder Only

Knowledge cutoff2025-08