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LatestOpenAIgpt-oss-20b
OpenAIReasoning

OpenAI Releases 21B Open-Weight MoE Model

The new `gpt-oss-20b` is an Apache 2.0-licensed Mixture-of-Experts model designed to run efficiently on consumer-grade hardware.

Aug 4, 2025
Major releaseApache 2.0
gpt-oss-20b

OpenAI has released gpt-oss-20b, a new open-weight model that brings a powerful architecture to more accessible hardware. The model is a Mixture-of-Experts (MoE) with approximately 21 billion total parameters and is available under the permissive Apache 2.0 license, encouraging broad community use and adaptation.

The most significant aspect of this release is its focus on efficiency. MoE models achieve high performance by selectively activating only a fraction of their total parameters for any given input, which can drastically lower computational requirements compared to dense models of a similar size. This design makes gpt-oss-20b particularly relevant for developers and researchers working with consumer-grade GPUs.

Capabilities and Specifications

Beyond its architecture, gpt-oss-20b features a large 131,072-token context window, enabling it to process and reason over very long documents or complex conversations. Its primary focus on reasoning suggests it is well-suited for tasks that require logical deduction and problem-solving.

This release provides a powerful new tool for building sophisticated AI applications on more widely available hardware. Developers can access the model weights, technical details, and usage instructions on the official Hugging Face repository.

Sources

  • openai/gpt-oss-20b

    Hugging Face

    Visit
OlderOpenAI Releases Its First Open-Source MoE ModelOpenAI · Reasoning · last yearNewerGoogle Releases Gemma 3 270M for On-Device AIGoogle DeepMind · Text / LLM · last year

Get the model

Hugging Face

Specs

Parameters21B · MoE
Active params3.6B active
Context window131K tokens
Size22.7 GB
PrecisionINT8
ArchitectureGptOssForCausalLM
LicenseAPACHE-2.0
Downloads2.5M
Likes5.5K

Can you run it?

Runs on a laptop — about 13.9 GB as published.

  • MXFP4 4-bit (as published)

    16 GB GPU (RTX 4080 / 5070 Ti) · 24 GB Mac

    13.9 GB
Your machine
GGUF builds
  • Mixture-of-experts: all 20.9B parameters must be resident even though only 3.6B are active per token — active count affects speed, not memory.
  • Published weights are already quantized (MXFP4 4-bit); smaller builds are not assumed.
  • KV cache sized for 8,192 tokens of context; longer prompts need proportionally more.

Based on Hugging Face weights metadata. Assumes an 8K context and ~1 GB runtime overhead; actual needs vary. How we estimate


Modalities

Text / LLMReasoning
2 versions — view changelog

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