OpenAI released two open-weight language models for the first time since it rolled out GPT-2 in 2019. The text-only models are called gpt-oss-120b and gpt-oss-20b, and are designed to serve as lower-cost options that developers, researchers and companies can easily run and customize, OpenAI said. Open-weight models can offer transparency and control, but they are different from open-source models, whose full source code becomes available for people to use and modify. The company collaborated with Nvidi, Advanced Micro Devices, Cerebras, and Groq to ensure the models will work well on a variety of chips. OpenAI said that it carried out extensive safety training and testing on its open-weight models. OpenAI said people can download the weights for gpt-oss-120b and gpt-oss-20b on platforms like Hugging Face and GitHub under an Apache 2.0 license. The models will be available to run on PCs through programs such as LM Studio and Ollama. Cloud providers Amazon, Baseten and Microsoft are also making the models available. Both models can handle advanced reasoning, tool use and chain‑of‑thought processing, and are designed to run anywhere — from consumer hardware to the cloud to on-device applications. Users can run gpt-oss-20b on a laptop, for instance, and use it as a personal assistant that can search through files and write, OpenAI said.