Why chatbots love the em dash
Nobody outside the AI labs knows for sure. The usual explanations are that edited books and articles in the training data use dashes heavily, and that human raters tended to prefer replies that read as polished. Both are plausible, and neither is proven. What's easy to see is the result: dashes in most sentences, often in pairs, doing the job a comma would do.
When to keep a dash
A dash works when you want a sharp break, like an aside that interrupts a sentence or a punchline at the end. The problem is a dash in every sentence, because then none of them stand out. Keep the one or two that earn it and turn the rest into commas or periods.
What to use instead
- Comma for a light pause or an aside that belongs in the sentence.
- Period when the dash is joining two complete thoughts.
- Colon before an explanation, an example or a list.
- Parentheses for an aside the reader could skip.
Em dash, en dash, hyphen
The em dash (—) is the long one. The en dash (–) joins ranges, like 2020–2026. The hyphen (-) joins words, like well-known. Many chatbots type the em dash directly; people often type two hyphens (--), which this checker also counts.
Questions
Why does ChatGPT use so many em dashes?
Nobody outside the AI labs knows for sure. Likely reasons: edited books and articles in the training data use them heavily, and human raters may have preferred replies that read as polished. Both are plausible; neither is proven.
Does using em dashes mean a text was written by AI?
No. Writers have used em dashes for centuries, and many careful human writers use them a lot. A high count is a reason to reread, not evidence of who wrote the text.
How many em dashes is too many?
There's no fixed number. Naturable flags a draft when it has at least 3 em dashes and 8 or more per 1,000 words. That's our starting threshold, not a rule of grammar.
What can I use instead of an em dash?
A comma for a light pause, a period for a hard break, a colon before an explanation or list, or parentheses for an aside.
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