Clean Up Em Dashes and Other AI Writing Tells
Large language models were trained on heavily edited prose, so they reach for the em dash far more often than most people write by hand. That habit has become one of the more obvious signs a paragraph came from ChatGPT, Claude, Gemini, or a similar tool. This cleans it up in one pass, alongside a handful of other characters AI writing and word-processor exports tend to leave behind.
Paste your draft on the left, choose what the em dash should become on the right, and turn on whichever of the extra cleanup toggles you need. The result updates as you type or change a setting, so you can copy it out the moment it looks right.
What exactly counts as an "em dash" here?
The em dash (—) is the long dash used to set off a clause or add emphasis mid-sentence. It's longer than a hyphen (-) and longer than an en dash (–), which is normally reserved for ranges like "2020–2025." This tool targets the em dash by default; check "Also replace en dashes" if you want the shorter en dash cleaned up the same way.
What are my replacement options?
Hyphen swaps the dash character directly for a plain hyphen and leaves the rest of your spacing untouched — the safest, most literal option. Comma and Space both treat the dash as a pause and absorb one adjacent space on each side into the replacement, so a normally-spaced dash comes out clean. Nothing (remove) drops the dash character itself but still leaves a single space behind, so two words that were separated by a dash don't get jammed together into one.
What do the other cleanup options do?
Smart quotes converts curly quotation marks (" " and ' ') into their plain, straight equivalents. Ellipsis character replaces the single "…" character with three separate periods. Non-breaking spaces swaps the invisible non-breaking space some editors insert for a normal space. Zero-width characters deletes invisible formatting characters outright, with nothing put in their place, since they're never meant to be visible in the first place.
Why do AI tools use em dashes so much?
Language models are trained on large volumes of professionally copyedited text — books, journalism, essays — where the em dash is standard, correctly-used punctuation. The models pick up that stylistic habit and reproduce it far more often than most people write it themselves, which is part of why heavy em-dash use has become a widely-noticed signal of AI-generated text.
Does this work on text from any AI tool?
Yes — it operates purely on the characters in your text, regardless of where they came from. ChatGPT, Claude, Gemini, Copilot, and Perplexity all produce similar dash-heavy output, and the same cleanup applies equally to text pasted from Word, Google Docs, or any webpage.
Related tools
- Remove Text Formatting — strip all styling from pasted rich text.
- Whitespace Remover — collapse extra spaces throughout a block of text.
- Plain Text Converter — convert rich text into clean plain text.
- Find and Replace Text — swap out any other character or phrase.
Last reviewed: August 2026