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GPT-OSS-120B

OpenAIOpen WeightsVerified

GPT-OSS-120B is a state-of-the-art open-weight language model that delivers strong real-world performance at low cost. This 120 billion parameter mixture-of-experts model achieves near-parity with OpenAI o4-mini on core reasoning benchmarks while running efficiently on a single 80 GB GPU. It was trained using reinforcement learning and techniques informed by OpenAI's most advanced internal models, including o3 and other frontier systems.

2025-08-05
117B total (5.1B active per token)
Mixture of Experts Transformer
Apache-2.0

Specifications

Parameters
117B total (5.1B active per token)
Architecture
Mixture of Experts Transformer
License
Apache-2.0
Context Window
128,000 tokens
Type
text
Modalities
text

Benchmark Scores

Massive Multitask Language Understanding (MMLU) tests knowledge across 57 subjects including mathema...

GPQA80.1

Graduate-level Problems in Quantitative Analysis (GPQA) evaluates advanced reasoning on graduate-lev...

A challenging benchmark of novel problems designed to test the limits of AI capabilities....

American Invitational Mathematics Examination (AIME) 2024 problems....

American Invitational Mathematics Examination (AIME) 2025 problems....

Advanced competitive programming benchmark for evaluating large language models on algorithmic probl...

Tool Augmented Understanding Benchmark (TAU-bench) evaluates models on their ability to use tools....

Advanced Specifications

Model Family
gpt-oss
API Access
Not Available
Chat Interface
Not Available
Variants
MXFP4 quantized
Hardware Support
NVIDIAAMDCerebrasGroqONNX Runtime

Capabilities & Limitations

Capabilities
chain-of-thought reasoningtool useweb searchpython code executionfunction callingstructured outputsvariable reasoning effortagentic workflowscompetition mathematicscodingscientific reasoninglow-latency inference
Known Limitations
Chain-of-thought may contain hallucinated or harmful contentCoT should not be directly shown to usersMay include language that doesn't reflect OpenAI's safety policiesRequires safety monitoring for CoT content
Notable Use Cases
Agentic workflowsCompetition mathematicsScientific researchCode generation and debuggingComplex reasoning tasksTool-assisted problem solvingOn-premises deploymentCustom fine-tuningResearch and development
Function Calling Support
Yes
Tool Use Support
Yes

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