This page converts U+2014 EM DASH, U+2013 EN DASH and eight rarer dash lookalikes to plain hyphens. The sample shows the classic pasted-flag failure. Everything runs in your browser — nothing is uploaded.
The long typographic dash — this one — used for asides and breaks in prose. Its shorter sibling U+2013 (en dash) marks ranges like 10–25. Both are correct typography, and both are entirely different characters from the ASCII hyphen-minus - that code and command lines expect.
Word, Google Docs, Outlook and macOS/iOS autocorrect turn -- into an em dash as you type. Publishing tools and many websites do the same, so command-line instructions in blog posts often ship with em dashes where double hyphens belong. LLM-generated text is famously em-dash-heavy too.
The classic: copy npm install —save-dev or curl —verbose from a formatted page and the tool reports an unknown argument, because —save-dev is not --save-dev. En dashes hiding in version ranges, config values and spreadsheet numbers cause quieter failures. ASCII-only pipelines (older terminals, some log processors, legacy databases) mangle them into mojibake like â.
Paste the text above — every dash variant is highlighted in blue and converted to a plain hyphen in the cleaned output. One caveat: an em dash becomes one hyphen, and most long CLI flags want two (--save-dev), because autocorrect originally ate -- to make the em dash. The x-ray shows exactly what was there so you can tell. If you only want dashes fixed, untick the other rules.
Guides for the common cleanup jobs — what the source puts into your text, exactly what it breaks, and the tool preloaded with a demonstration:
AI-generated text · Text copied from Word / Google Docs · Text copied from a PDF · Pasted code that won’t run · CSV & spreadsheet data · Invisible watermarks · Many files at once (batch)
Dedicated pages for the usual suspects — what each one is, where it sneaks in from, the exact errors it causes, and how to find it in your editor:
Zero-width space (U+200B) · Non-breaking space (U+00A0) · Byte order mark (BOM) (U+FEFF) · Soft hyphen (U+00AD) · Smart quotes · Em dash (U+2014) · Narrow no-break space (U+202F) · Ideographic space (U+3000) · Zero-width joiner (U+200D) · Zero-width non-joiner (U+200C) · Word joiner (U+2060) · Right-to-left override (U+202E) · Left-to-right mark (U+200E) · Line separator (U+2028) · Variation selector-16 (U+FE0F) · Object replacement character (U+FFFC) · Hangul filler (U+3164) · Braille pattern blank (U+2800) · Ligatures · Minus sign (U+2212)
Страницы на русском — те же инструменты с переведёнными правилами и примерами под задачу:
Невидимые символы в тексте · Убрать невидимые символы · Почистить текст нейросети · Неразрывные пробелы в числах · Текст из Word · Код не запускается