gpt-oss-120b on Fireworks AI

Name: gpt-oss-120b on Fireworks AI
Brand: OpenAI
SKU: gpt-oss-120b-fireworks-ai
Price: 0.15 USD

ServerlessOpen Source

Last refreshed 2026-04-19. Next refresh: weekly.

Why use gpt-oss-120b on Fireworks AI?

Fireworks AI offers gpt-oss-120b with pay-as-you-go pricing at $0.15/1M input tokens. Fireworks AI offers a generative AI platform as a service, focusing on rapid product iteration and cost-efficient AI deployment.

Compare gpt-oss-120b across 13 providers to find the best fit for your use case

Input / 1M

$0.15

Output / 1M

$0.60

Cache

Not sourced

Batch

Not sourced

Setup recipe

Python + curl

Install

pip install openai

Auth

export FIREWORKS_API_KEY=...

Call

import os
from openai import OpenAI
client = OpenAI(
    api_key=os.environ["FIREWORKS_API_KEY"],

Model ID

accounts/fireworks/models/gpt-oss-120b

Request example

import os
from openai import OpenAI

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

Gotchas

Use provider model ID "accounts/fireworks/models/gpt-oss-120b", not the LLMReference slug "gpt-oss-120b".
Fireworks model IDs use "accounts/fireworks/models/{model-name}" format, e.g. "accounts/fireworks/models/llama4-scout-instruct-basic" or "accounts/fireworks/models/deepseek-r1".
The examples expect FIREWORKS_API_KEY; rename it only if your application config maps the new variable.

Compare gpt-oss-120b Across Providers

Provider	Input (per 1M)	Output (per 1M)
Cloudflare Workers AI	$0.35	$0.75
OpenRouter	$0.04	$0.18
Together AI	$0.15	$0.60
Fireworks AI	$0.15	$0.60
GCP Vertex AI	$0.09	$0.36

View all 13 providers →

Pricing

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.

Get Started

Model Card Docs Portal Pricing

Model Specs

Released2025-08-05

Parameters120B

Context131k

ArchitectureDecoder Only

Knowledge cutoff2025-08