gpt-oss-120b

GPT OSS 120B

gpt-oss-120b
gpt-oss-120b is an open-weight, 117B-parameter Mixture-of-Experts (MoE) language model from OpenAI.
Intelligence
Speed
Price
$0.05 • $0.25
Input
Output

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 to run on a single H100 GPU with native MXFP4 quantization. The model supports configurable reasoning depth, full chain-of-thought access, and native tool use, including function calling, browsing, and structured output generation.

131000 context window
100000 max output tokens
knowledge cutoff

Modalities

Text

Input and output

Image

Not supported

Audio

Not supported

Video

Not supported

Endpoints

Chat Completions

v1/chat/completions

Responses

v1/responses

Realtime

v1/realtime

Assistants

v1/assistants

Batch

v1/batch

Fine-tuning

v1/fine-tuning

Embeddings

v1/embeddings

Image generation

v1/images/generations

Videos

v1/videos

Image edit

v1/images/edits

Speech generation

v1/audio/speech

Transcription

v1/audio/transcriptions

Translation

v1/audio/translations

Moderation

v1/moderations

Completions (legacy)

v1/completions

Features

Streaming

Supported

Function calling

Not supported

Structured outputs

Not supported

Fine-tuning

Not supported

Distillation

Not supported

Tools

Tools supported by this model when using the Responses API.

Web search

Not supported

File search

Not supported

Image generation

Not supported

Code interpreter

Not supported

Computer use

Not supported

MCP

Not supported