ChatGPT’s custom GPTs, now available as of December 2025, allow Australian businesses to create tailored versions of ChatGPT for specific tasks without needing coding experience. These customisations function as dedicated AI assistants trained on your data and instructions, accessible through the ChatGPT interface.
Currently, creating a custom GPT involves using the ‘Create a GPT’ option within ChatGPT Plus. You define its personality, instructions, and knowledge base by uploading files (up to 20MB per file – supporting PDF, TXT, CSV formats) or providing specific knowledge directly within the GPT builder. In 2026, OpenAI plans to increase the file upload limit to 100MB and introduce support for more file types, including DOCX and XLSX. Australian businesses can use this to train a GPT on product catalogues, internal documentation, or brand guidelines. Access to the GPT builder is included with a ChatGPT Plus subscription, which costs AU$30 per month as of December 2025.
Custom GPTs can then be used internally by teams or, with appropriate privacy considerations, offered to customers as a specialised support tool. The key benefit is increased efficiency and consistency in responses, as the GPT operates within the defined parameters and knowledge base, offering a focused AI experience.
