Recently, Sam Altman, CEO of OpenAI, stated on social media platform X that users can now choose to not use em dashes in ChatGPT's custom instructions. He said, "This finally makes it do what it should."  

ChatGPT's custom instructions allow users to adjust how the AI responds, and this feature can be found in the personalization options within the settings menu. Altman added, "It's a small but happy victory."  

ChatGPT

Image source note: The image is AI-generated, and the image licensing service is Midjourney

As ChatGPT becomes more popular, em dashes have become increasingly common in online writing, becoming a notable characteristic of AI-generated text. However, many users found it difficult to make ChatGPT avoid using em dashes. One user wrote on a blog, "I tried various methods, but I just couldn't get it to stop using them."  

On social media, renowned author Chip Huyen said, "I would pay $100 to anyone who can teach me how to stop ChatGPT from using em dashes. It's driving me crazy."  

Analysis shows that one reason for ChatGPT's frequent use of em dashes is the large amount of modern prose in its training data, which often uses em dashes for rhythm, emphasis, and smooth transitions. Aileen Gallagher, a journalism professor at Syracuse University, pointed out, "If an AI primarily relies on magazine or blog writing, both styles tend to favor em dashes."  

Additionally, em dashes effectively connect or interrupt thoughts, reducing additional structure, and are also very efficient from the perspective of generating tokens. Overuse of em dashes has also sparked a lot of jokes and memes on social media.  

Some users feel this phenomenon is unfair, saying, "Now everyone thinks I used ChatGPT to generate my text, which is really annoying." One user mentioned, "I often use em dashes in emails and writing — maybe not correctly. Now everyone assumes I input everything into ChatGPT."  

Notably, Altman announced this update the day after OpenAI released the GPT5.1 model. This version is an upgrade to the GPT-5 series, adding new reasoning capabilities, improving processing speed for simple tasks, and expanding ChatGPT's personalization tools.  

Key points:  

✨ Users can now choose to stop using em dashes in ChatGPT.  

📈 Altman said this feature is a positive response to user feedback.  

🆕 The release of the GPT5.1 model brings more personalization options and improved performance.