If you’ve been working with ChatGPT for a while, you’ve probably noticed a strange little pattern : every few sentences, there it is — the em dash.
The good news? You can train ChatGPT to stop, or at least reduce them.
In this guide, you’ll learn how much control you really have over its punctuation and prompts to minimize them.
Can you really remove em dashes from ChatGPT output?
You can instruct ChatGPT to avoid em dashes. However, even when asked, the model sometimes slips in em dashes or mis- uses hyphens/dashes. LLMs are not 100% obedient. So you still need to check manually
The prompts given below are not a perfect auto-fix, but they can help.
ChatGPT Prompts to Remove Em Dashes
Below are prompt you can use to steer ChatGPT away from em dashes and keep your writing sounding human.
1. Basic Direct Instruction Prompt
Give ChatGPT a simple, no-fuss instruction: just don’t use em dashes.
Please write this section without using any em dashes (—). Use commas or periods instead.
Text/topic: “[Paste or describe]”
2. Format-Enforcement Prompt
Tells ChatGPT not just to avoid em dashes, but to check its own output or provide a version without them. That increases the chance it follows the instruction very precisely.
- List any em dashes (—) found in the draft.
- Provide a second version of the same text with all em dashes replaced by commas or periods.
Draft: “[Insert here]”3. Troubleshooting Prompt
What it does: When ChatGPT keeps inserting em dashes despite instructions (which many users report). This prompt can make ChatGPT more thouthful and reduce its stuborness.
I told you not to use em dashes (—) but your draft still has them.
Please explain why em dashes appeared, then rewrite the section removing all em dashes. 
