The ChatGPT em dash
and five ways to rewrite it
Six of twelve plain ChatGPT-style drafts used an em dash. Here are the five rewrites Keyiku reaches for, shown on real lines.
The em dash was the most common tell in our test. We gave one model twelve ordinary briefs with a plain prompt, and six of the drafts used one. The dash itself is a fine piece of punctuation. The trouble is how often it shows up, and that readers have started to treat it as a signature.
We do not know exactly why models reach for it so often. What we can tell you is what to do with each one. Keyiku flags every em dash, spaced en dash and double hyphen, then rewrites the sentence one of five ways.
1. A period
Most dashes join two thoughts that each deserve a sentence. Split them, and the second thought gets its own weight.
Your Omaha practice’s online booking takes 9 clicks—and breaks on phones.
Your booking page takes 9 clicks. On a phone, it breaks.
2. A comma
When the part after the dash just adds a detail, a comma carries it with less drama.
Stop by for your morning coffee—now an hour earlier.
Starting Monday, the 14th Street shop opens at 6am, an hour earlier.
3. A colon
A colon promises that what follows explains what came before. Use it when the second half is the proof.
Protecting Kansas City Since 2004—Over 2,000 Roofs Replaced.
Kansas City since 2004: over 2,000 roofs replaced
4. Parentheses
If the aside could be whispered, put it in parentheses. Readers skim them, so keep the main claim outside.
Our dog daycare gives your pup a place to play—and you a way to peek in, with webcams in every room.
Your dog plays all day (and every room has a webcam, so you can check in from work).
5. Rebuild the sentence
Sometimes the dash is covering for a sentence that never knew what it wanted to say. Start again from the one thing the reader should take away.
Discover how your home could use less energy—with a free energy audit.
Start with a free energy audit of your home Get my audit
Serving Lincoln, Nebraska for 15 years, our two-truck crew keeps lawn care simple—and texts you a photo when the job’s done.
Know when your lawn is done, even while you’re out Our Lincoln lawn crew shows up on time and texts you a photo when the job is done.
Telling ChatGPT to stop
Adding "no em dashes" to your prompt cuts most of them, and it is worth doing. Then search the draft for the character before you send it. A rule in a prompt is a request. A check after the draft is a guarantee, which is why Keyiku runs one on every version it writes.
AI tellsNov 8, 2026ChatGPT words to avoidand what to write insteadThe words and phrases Keyiku flags on every draft, each with a plain swap, plus a prompt you can paste into ChatGPT tonight.
CraftNov 8, 2026How to make ChatGPTsound less like AIOne real brief, walked through Keyiku step by step: the plain draft, the flags, the plan, three drafts, the editor’s scores and the final line.