What is OpenAI doing to address ChatGPT's em-dash issue?

OpenAI has introduced new customization options that allow ChatGPT users to stop the AI from overusing em-dashes in its generated writing.

What are some theories behind ChatGPT's fondness for em-dashes?

Researchers have proposed that the em-dash's prevalence in 19th-century books, which are often used as training data for large language models, and its widespread use on Medium blogs, another common source of OpenAI's training data, may have contributed to ChatGPT's em-dash fixation.

Home / Technology / OpenAI Fixes ChatGPT's Em-Dash Obsession with Customization

OpenAI Fixes ChatGPT's Em-Dash Obsession with Customization

Q: Why has ChatGPT's em-dash usage become a problem?

The widespread use of em-dashes in ChatGPT's output has put some writers in a difficult position, as the punctuation mark has become associated with AI-generated content rather than human-written work.

15 Nov

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Summary

ChatGPT's overuse of em-dashes was a widespread issue
OpenAI now allows users to customize settings to stop em-dash usage
Em-dashes have become associated with AI-generated writing

OpenAI Fixes ChatGPT's Em-Dash Obsession with Customization

As of 2025-11-15T18:53:06+00:00, OpenAI has stepped in to address the ongoing issue of ChatGPT's overuse of em-dashes in its generated writing. According to CEO Sam Altman, users can now customize their settings to prevent the chatbot from using em-dashes going forward.

The em-dash fixation has proven controversial since it first started appearing in ChatGPT's responses. Research from The Washington Post showed that at one point this year, almost half of ChatGPT's output included the punctuation mark, a nearly fivefold increase compared to 2024. Many ChatGPT users had taken to social media to complain about the difficulty in getting the chatbot to stop using em-dashes, despite trying various prompts.

The widespread use of em-dashes in ChatGPT's writing has put some writers in a difficult position, as the punctuation mark has become associated with AI-generated content rather than human-written work. Some users have even resorted to avoiding em-dashes altogether to prevent unfair accusations.