What the ChatGPT watermark checker scans
The words you see are only one part of a copying workflow. A browser can also place styled HTML on the clipboard, and the text itself can contain spaces or formatting controls that look ordinary on screen. These layers have different consequences: unwanted bold text belongs to the formatting layer, while an unexpected character inside an identifier belongs to the text layer.
If you are pasting into a newsletter, first decide whether headings and links should survive. If you are pasting a value into a database or a form, inspect the exact characters instead. Removing rich formatting and removing Unicode characters are separate choices; neither requires rewriting the answer.
Hidden characters vs OpenAI text watermarking
A report of U+200B tells you that a zero-width space exists at a particular position. It does not tell you which app inserted it, whether the author used AI, or what an AI detector will say. A non-breaking space can arrive from a web page, a document editor, or a manually typed shortcut. The same caution applies when a copied HTML fragment contains data attributes: interface markup is not a universal authorship certificate.
OpenAI’s October 2026 text provenance announcement describes a statistical watermark and a phased rollout, not a universal hidden-character marker. This tool does not verify that signal. It measures the characters it can actually inspect; the linked guide explains the current announcement and its scope.
How to check and clean copied ChatGPT text
Compare the original and cleaned versions before replacing your draft. Keep deliberate spacing in addresses, product names, and number-unit pairs where a line break would be confusing. Check multilingual passages and emoji after any aggressive cleanup. If your problem is visible Markdown, use the formatting remover rather than repeatedly deleting invisible characters.
For research or published work, keep citations and review the substance of the answer separately. A cleaner can make text easier to move between applications; it cannot verify facts, establish permission to reuse material, or satisfy a disclosure policy on your behalf.
Sources & further reading
Primary references for the technical points in this guide.