Text cleaning guides & tools

Choose a starting point

• Text looks normal but search fails: check for zero-width spaces.
• Lines refuse to wrap: replace non-breaking spaces.
• Chatbot answers contain asterisks and headings: convert Markdown to plain text.
• A copied PDF has broken words: clean text copied from a PDF.
• You want to understand a scan result: look up the Unicode character.

Clean AI Text

Prepare chatbot drafts for an editor, or learn what a character scan can tell you about an AI watermark.

• AI Text Cleaner: Fix ChatGPT, Claude & Gemini Output in One Click

  Free AI text cleaner: strip hidden Unicode (U+202F), smart quotes, and em dashes from ChatGPT, Claude, or Gemini text. 100% in-browser, nothing uploaded.

• AI watermark checker: inspect hidden characters

  Inspect text for supported hidden Unicode characters with a code-point report. Learn what a character checker can verify and why it cannot detect AI authorship.

• What's Inside AI Text, and Why You'd Clean It

  AI output carries four layers of baggage: hidden Unicode, lookalike spaces, smart typography, and markdown residue. What each layer is, and where it comes from.

• How to Clean Text Copied From Claude

  Claude output pastes with markdown symbols, curly quotes, and stray spacing left over. Clean it in your browser — free, and honest about the 2026 watermark.

• How to Clean Text Copied From Gemini

  Gemini output pastes with markdown symbols, dense tables, and stray spacing left over. Clean it in your browser — free, and honest about SynthID-Text.

• Remove hidden characters from ChatGPT text

  Clean hidden characters and unusual spaces from copied ChatGPT text. See what was changed and understand why Unicode cleanup cannot verify or remove every watermark.

• Remove Em Dashes from ChatGPT & AI Text

  A preprint measured 10.62 em dashes per 1,000 words in GPT-4.1 vs 3.23 for humans. Remove or replace every U+2014 in one click, plus Word and Docs fixes.

Hidden Characters

Find the code points behind failed searches, unexpected line wrapping, and invisible characters in copied text.

• ChatGPT Hidden Characters: What They Are and How to See Them

  Which hidden and special characters ChatGPT really outputs — U+202F, non-breaking spaces, smart quotes — why they appear, and 4 ways to make them visible.

• Remove BiDi & Directional Control Characters

  Strip hidden U+200E, U+200F and other directional control characters that flip your text or cause cursor glitches. Sanitize text for code and documents.

• Remove Invisible Characters from Text

  Instantly remove invisible characters, zero-width spaces, and hidden Unicode from any text — including ChatGPT output. Free, private, runs in your browser.

• Zero Width Space Remover (U+200B)

  Stop weird spacing and broken search results. Instantly identify and delete hidden zero-width spaces (U+200B) from your text for a clean paste.

Fix Formatting

Choose a fix for pasted documents, Markdown, unusual spaces, or punctuation that breaks a destination app.

• Clean Pasted Text: The Universal Sanitizer

  The all-in-one tool to sanitize text from any source. Remove invisible characters, fix spacing, and normalize typography — 100% in your browser, always free.

• Fix Weird Spacing When Pasting Text

  Why does your text paste with weird gaps? Instantly normalize spaces, remove non-breaking spaces (NBSP), and fix irregular line breaks — free, in-browser.

• Markdown to plain text converter

  Convert Markdown to plain text in your browser. Remove common heading, bold, and link syntax from copied drafts, then copy or download the result for free.

• Normalize Quotes, Dashes & Ellipses

  Convert curly quotes to straight quotes and em dashes to hyphens. Clean typography for markdown, code, and plain-text editors — free and instant.

• Paste AI Text into Word, Google Docs & Notion Without the Mess

  Why ChatGPT text pastes with asterisks, ### headers, curly quotes, and hidden characters — and the exact fix for Word, Google Docs, Notion, email, and CMS.

• Clean text copied from a PDF

  Clean text copied from a PDF: remove soft hyphens and hidden characters, normalize spaces, and fix line endings. Free browser tool with a report of changes.

• Remove & Convert Non-Breaking Spaces (NBSP)

  Convert non-breaking spaces (NBSP, U+00A0) into standard spaces. Fix text that won't wrap and remove un-deletable gaps from pasted content — free, in-browser.

Guides

Understand the copy-paste pipeline and choose settings that fit the document you are working on.

• ASCII Smuggling Explained: How Invisible Unicode Hides Data

  ASCII smuggling hides invisible instructions inside Unicode tag characters (U+E0000-U+E007F). How the attack works, real exploits, and how to detect it.

• Why Invisible Characters Break ATS Resume Parsing

  Copy-pasting a resume from ChatGPT, Claude, or Word can carry invisible Unicode characters that break ATS keyword parsing. How it happens, and the fix.

• The CleanPastedText browser extension

  Clean hidden Unicode characters and AI watermarks from a Chrome toolbar popup or side panel. Same engine as the website, and no access to the pages you visit.

• C2PA Content Credentials Explained

  What C2PA Content Credentials are, how the signed manifest works, and why a screenshot or social-media upload destroys them. With primary sources.

• EU AI Act Watermarking Rules: What Article 50(2) Requires

  What EU AI Act Article 50(2) requires for AI-generated content as of August 2, 2026 — and why removing hidden Unicode characters doesn't satisfy it.

• Hidden Characters and Screen Reader Accessibility

  Do hidden Unicode characters break screen readers? What WCAG's own failure techniques (F32, F33) and accessibility research say, and how to check your text.

• Homoglyph Attacks: How to Detect Lookalike Unicode Characters

  Homoglyph attacks swap letters for lookalike Unicode, like Cyrillic а (U+0430) for Latin a. How the attack works, real cases, and how to spot it.

• How Do AI Text Detectors Work?

  How Turnitin, GPTZero, and Originality.ai actually score AI-written text — perplexity, burstiness, classifiers — and how accurate they really are, with sources.

• How to Clean AI-Generated Text Before Publishing

  Clean AI-generated text before publishing: remove hidden Unicode, fix spacing and typography, preserve wording, and paste safely into any CMS.

• Fix “Unexpected Token in JSON at Position 0”

  JSON.parse fails at position 0 when a file starts with a byte order mark (U+FEFF). The exact cause, the fix in JavaScript and Python, and how to prevent it.

• Paste as Plain Text: Keyboard Shortcuts for Every App

  The paste-without-formatting shortcut for Windows, Mac, Chromebook, Word, Google Docs, Gmail, and Slack — and why it still leaves hidden characters behind.

• Fix “SyntaxError: Invalid Character” in Python

  Python's invalid character SyntaxError happens when a copy-pasted zero-width space, BOM, or NBSP lands outside a string. The exact cause, verified output, and fix.

• The Regex That Actually Removes Invisible Unicode Characters

  Copy-paste regex to strip zero-width spaces, BOMs, and invisible Unicode characters in JavaScript and Python — and why \s and a bare \p{Cf} both miss cases.

• How to Sanitize Copied Text for Code, JSON & CSV

  Sanitize copied text for code, JSON, CSV, forms, or databases. Remove invisible Unicode and normalize risky characters locally, with a full report.

• SynthID-Text Explained

  SynthID-Text biases word choice with a secret key instead of adding characters. How tournament sampling works, who uses it, and why no cleaner can remove it.

• Trojan Source: Invisible Unicode Vulnerabilities in Source Code

  Trojan Source hides Unicode BiDi characters in code so it compiles differently than it displays. How CVE-2021-42574 works and how to check for it.

• Invisible Characters in URL Slugs Break Links and Split Duplicates

  A zero-width space or NBSP pasted into a URL slug creates a link that looks correct but 404s or splits into a duplicate URL. How it happens and how to fix it.

• What Is an AI Text Watermark? Character-Level vs Statistical

  AI text watermarks work two ways: hidden Unicode characters you can strip, and statistical word-choice patterns (SynthID) you cannot remove. With sources.

• Why Does My Text Paste Weird?

  An in-depth guide to Unicode, invisible characters, and why copying from PDFs, websites, and AI chatbots causes weird spacing and formatting issues.

• Words ChatGPT Overuses (And Why)

  Researchers measured "delve" at ~25x its normal rate in 14 million papers. The research-backed list of words ChatGPT overuses, why it happens, and plainer swaps.

Reference

Look up supported Unicode characters, their normal uses, and the effect of removing them.

• How CleanPastedText Works

  The exact pipeline CleanPastedText runs: detection-first scanning, emoji-safe stripping, NFKC normalization. Deterministic, client-side, nothing uploaded.

• Invisible Unicode Characters: The Complete List

  The complete table of invisible Unicode characters: zero-width spaces, U+202F, BiDi controls, tag characters, variation selectors — and why each one matters.

• Zero Width Non-Joiner (U+200C)

  What the zero-width non-joiner (U+200C) does, why Persian and Indic text need it, and how to strip it from other text without breaking those words.