Have you noticed a particular punctuation mark showing up frequently in AI-generated content?
The em dash—that long, versatile line—has become a signature of large language models like ChatGPT and Claude. While useful for emphasis and structuring thoughts, its constant appearance can make writing feel repetitive and, frankly, a bit robotic.
Learning to manage this quirk is essential for anyone aiming to produce content that reads as if it were written by a human, not a machine.
By understanding why AIs favor this punctuation and how to control it, you can refine your outputs for a more natural and authentic feel.
Key Takeaways
- Understand the Em Dash: Learn what an em dash is and why AI models tend to overuse it as a simple way to connect ideas.
- Fix Overuse in AI: Discover specific techniques, including custom instructions, prompt engineering, and editing strategies, to reduce unwanted em dashes in your generated text.
- Adopt Best Practices: Gain insights into maintaining balanced and natural punctuation without overcorrecting or sacrificing clarity.
- Improve Your Content: Apply these methods to create higher-quality, human-like text that avoids common AI writing tells.
What Are Em Dashes?
An em dash (—) is a punctuation mark used to create a strong break in a sentence. It’s longer than a hyphen (-) or an en dash (–). Writers use it to signal an interruption, add emphasis to a point, or set off an explanatory clause. It’s a powerful tool for adding style and voice to writing.
How to Permanently Stop ChatGPT from Using Em Dashes Custom Instruction Fix That Works
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Correct Usage Example:
The final results were better than we ever imagined—a true testament to the team's hard work.
Here, the em dash adds emphasis and separates the main clause from the concluding thought.
However, AI models often overuse it, creating a "dash density" that feels unnatural.
Because their training data includes vast amounts of polished, edited text where em dashes are used for stylistic effect, the models learn to replicate this pattern.
They often use it as a catch-all solution to connect related ideas, avoiding the more complex rules of commas or semicolons.
Overuse Example:
AI-generated content—which often relies on predictable patterns—can be easily identified by its overuse of certain punctuation—like the em dash.
This sentence feels clunky and repetitive due to the multiple dashes. A human writer would likely rephrase it.
How to Fix Em Dashes in ChatGPT and Other AI
Controlling em dash usage requires a proactive approach. You can guide the AI before it generates text and clean up the output afterward. Here are three effective methods.
Custom Instructions
One of the most effective ways to manage em dashes in ChatGPT is by using its "Custom Instructions" feature.
To set this up, go to your ChatGPT settings and find the custom instructions section. In the part that asks how you want ChatGPT to respond, add a clear directive like:
"Do not use em dashes (—) in your output. Use commas, periods, or parentheses instead. Replace every em dash before responding."
First go to chatgpt.com, Sign-in with your account and from left bottom, click on your username and select "Personalization";
Next, Under the custom instructions option, add the following.
This allows you to set standing orders for all your future conversations.
By telling the model to avoid this punctuation, you can significantly reduce its appearance from the start.
This simple instruction tells the model your preference for punctuation, and it will apply this rule to its responses, saving you from having to repeat the request in every prompt.
Prompt Engineering
For more direct control or when using models that lack a custom instructions feature, like Claude, prompt engineering is your best tool.
This means crafting your prompts to include specific rules about punctuation.
Start your prompt with a clear rule. For instance:
"Please write a blog intro about digital marketing trends. Important: Do not use em dashes (—) in your response. Use only commas and periods for separation."
You can also reinforce this instruction by providing an example of what you want and what you want to avoid. This is known as "few-shot prompting."
Example Prompt:
"I need a product description for a new coffee blend. Follow this rule: Never use the em dash.
Here is an example of what to avoid:
Our new coffee—a rich, dark roast—is perfect for your morning routine.
Here is an example of what to do:
Our new coffee, a rich and dark roast, is perfect for your morning routine.
Now, write the description."
This level of detail helps guide the AI to produce text that aligns perfectly with your stylistic needs.
Reviewing and Editing Outputs
No automated system is perfect, so a final review is always a good idea. Even with clear instructions, an em dash might slip through. Fortunately, fixing them is straightforward.
For shorter texts, a quick manual scan is all you need. When you spot an em dash, ask yourself if it's truly necessary.
Often, you can replace it with a comma, break the sentence into two, or rephrase the idea for better flow.
For longer documents, a "find and replace" function is your best friend. In Microsoft Word, Google Docs, or any other text editor, use Ctrl+H (or Cmd+H on Mac) to open the tool. Simply search for "—" and decide on a replacement.
You might replace it with a comma or review each instance individually to choose the best alternative. This simple step can clean up a lengthy document in seconds.
Best Practices for Natural Style
The goal is not to eliminate em dashes entirely but to use them purposefully. They are a valid and expressive part of the English language. When editing AI-generated content, focus on balance and readability.
- Don't Overcorrect: Avoid a blanket replacement of every em dash with a comma. This can lead to long, rambling sentences. Sometimes, the best solution is to split a complex sentence into two shorter, clearer ones.
- Limit Frequency: As a general rule, try to limit em dashes to no more than one per paragraph. This prevents the text from feeling stylistically repetitive.
- Vary Your Punctuation: Mix commas, parentheses, colons, and periods to create a more natural rhythm. Each has a specific function that can add nuance to your writing.
- Read It Aloud: The best way to check for natural flow is to read your text out loud. If it sounds awkward or you find yourself stumbling over punctuation, it’s a sign that the sentence structure needs work.
Final Thoughts
The overuse of em dashes is a small but telling sign of AI-generated content. By learning to manage it, you take a significant step toward creating text that is more polished, readable, and human. The techniques—from setting custom instructions to careful editing—give you greater control over the final output.
Ultimately, these AI models are tools. The real skill lies in guiding them effectively and refining what they produce. So, experiment with these methods, find what works for you, and continue to develop your ability to blend the power of AI with the nuance of human writing.
