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Em dash remover

Paste ChatGPT text and replace every em dash with a comma, a hyphen or an en dash — instantly, in your browser. Hidden characters go in the same click.

Replace each em dash with
Your text0 em dashes

Facts checked against the sources below on .

Why ChatGPT uses so many em dashes

Nobody outside OpenAI knows exactly why. Em dashes are common in the edited books and articles models learn from, and chat models lean on them to bolt an extra thought onto a sentence. Users found for a long time that asking ChatGPT to stop didn’t work. In November 2025 Sam Altman said that had been fixed — but only for instructions set in ChatGPT’s custom instructions.

The result is that the em dash has become the punctuation people most associate with AI writing, fairly or not. Plenty of human writers use it; the tell is the density, several to a paragraph.

Em dashes are not a watermark

The watermarks AI providers actually use are statistical. OpenAI’s textGrain, Google’s SynthID and Claude’s watermark live in which words the model chose, and OpenAI states that textGrain adds no unusual punctuation. So replacing em dashes changes how text reads, not whether a detector can find a watermark. For that, use the AI watermark remover, which rewrites the wording — the button under the result sends your text straight there.

Em dash, en dash or hyphen?

MarkNameUsed for
—Em dash (U+2014)Breaks or asides in a sentence — the mark ChatGPT overuses
–En dash (U+2013)Ranges (2019–2021); spaced, it’s the British style for a break
-Hyphen (U+002D)Joins words (well-known); what most people type for any dash

The tool replaces em dashes and spaced en dashes, which do an em dash’s job, and leaves unspaced en dashes alone because those mark ranges. A dash at the start of a line — dialogue, or a list written with dashes — becomes a hyphen whatever you choose, so lists stay lists.

How to stop ChatGPT writing em dashes

  1. Open ChatGPT’s settings → Personalization → Custom instructions.
  2. Add a line such as “Never use em dashes; use commas, colons or full stops instead.”
  3. Start a new chat. Instructions set there apply to every conversation; for text you already have, use the remover above.

FAQ

Is the em dash an AI watermark?+
No. A watermark is a hidden signal a detector can check, and OpenAI says its text watermark, textGrain, adds no unusual punctuation. The em dash is a style habit that readers have learned to associate with AI. Removing em dashes doesn’t remove a watermark, and a text full of them isn’t proof that AI wrote it.
How do I stop ChatGPT from using em dashes?+
Put it in your custom instructions — for example, “Never use em dashes.” In November 2025 Sam Altman said ChatGPT now follows that instruction when it is set in custom instructions; asking in a single prompt is less reliable. For text you already have, paste it above.
Which replacement should I choose?+
A comma suits most em dashes in the middle of a sentence, and a pair of em dashes around an aside becomes a pair of commas. Choose hyphen if you like the look of a dash but want plain ASCII, or en dash for the spaced British style. A dash that introduces an explanation or a list may read better as a colon — re-read those by hand.
Does it change anything else in my text?+
Only em dashes and spaced en dashes (which read as em dashes) are replaced; ranges like 2019–2021 stay. If “Also strip hidden characters” is on, invisible characters such as zero-width spaces are removed and no-break spaces become ordinary spaces.
Is my text uploaded?+
No. The em dash remover runs entirely in your browser. Nothing is sent anywhere unless you choose to send the result on to the rewrite tool.

Sources

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