GPT-3.5 Turbo fine-tuning and API updates
OpenAI has opened fine-tuning access for GPT-3.5 Turbo, allowing developers to customize the model with their own data for specific use cases. This extends fine-tuning capabilities previously available on older GPT-3 models to the more capable Turbo variant. The announcement also includes associated API updates to support this functionality.
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Customizing GPT-3 for your application
OpenAI announced fine-tuning capabilities for GPT-3, enabling developers to customize the model for specific applications via a single command. This feature allows users to adapt GPT-3's behavior to their use case by training on domain-specific data. The announcement marks an early milestone in making large language model customization accessible through an API.
Fine-tuning now available for GPT-4o
OpenAI has launched fine-tuning support for GPT-4o, its flagship multimodal model, as of August 20, 2024. This allows developers to customize GPT-4o on their own datasets via the OpenAI API. The release extends the fine-tuning capability previously available on GPT-3.5 and GPT-4 to the most capable model in OpenAI's lineup, enabling task-specific optimization at the frontier.
OpenAI Improves Fine-Tuning API and Expands Custom Models Program
OpenAI announced enhancements to its fine-tuning API giving developers greater control over the training process, alongside an expansion of its custom models program. The updates aim to provide more flexibility for enterprise and developer use cases requiring tailored model behavior. Specific new features include additional hyperparameter controls and tooling improvements, while the custom models program expansion opens new pathways for organizations to build bespoke models with OpenAI's assistance.
Introducing GPT-4.1 in the API
OpenAI is releasing GPT-4.1, a new family of models available via API to developers worldwide, featuring improvements in coding, instruction following, and long-context understanding. The release also includes GPT-4.1 nano, OpenAI's first nano-scale model. The models are positioned as developer-facing API products rather than consumer-facing releases.
GPT-3 Powers Over 300 Applications via OpenAI API
OpenAI reports that more than 300 applications are now using GPT-3 through its API to deliver search, conversation, text completion, and other AI features. The announcement highlights the growing commercial ecosystem built on top of GPT-3 as of early 2021. This represents an early milestone in API-based AI deployment at scale.
OpenAI DevDay: GPT-4 Turbo, Assistants API, and New Developer Products
OpenAI announced GPT-4 Turbo at DevDay, featuring a 128K context window and reduced pricing compared to GPT-4. The release also includes a new Assistants API for building agent-like applications, GPT-4 Turbo with Vision capabilities, and access to DALL·E 3 via API. These announcements collectively represent a significant expansion of OpenAI's developer platform.
Introducing vision to the fine-tuning API
OpenAI has extended its fine-tuning API to support multimodal inputs, allowing developers to fine-tune GPT-4o using both images and text. This enables customization of vision capabilities for domain-specific tasks. The update expands the existing text-only fine-tuning pipeline to handle image-text pairs.
Introducing GPT-5.1 for developers
OpenAI has released GPT-5.1 via API, positioned as an upgrade to GPT-5 with faster adaptive reasoning and improved coding performance. The release introduces new developer-facing tools including apply_patch and shell, along with extended prompt caching support. The announcement targets developers building on the OpenAI API platform.



