OpenAI’s GPT-5.3 Instant, the most widely used model in ChatGPT, cuts hallucinations by up to 26.8% compared to its predecessor, focusing on improving accuracy and conversational reliability rather than just speed. It enhances tone, relevance, and dialogue flow, resulting in fewer refusals and a more natural interaction style. The update balances online information with internal reasoning more effectively, thus delivering clearer, more useful answers promptly. While currently exclusive to the Instant model, OpenAI plans to upgrade other ChatGPT models soon. Despite improvements, some limitations remain, particularly in certain languages, and safety evaluations show mixed results in some sensitive content areas. OpenAI also indicated that GPT-5.4 could arrive sooner than expected.