Copilot watermark remover
Microsoft watermarks AI text in one documented place: since October 2026, its Windows AI text APIs (Phi Silica) hide the invisible sequence U+200B U+034F U+2060 U+200B in their output. Microsoft 365 Copilot’s documented watermarks cover images, audio and video, not text. Unmark finds and strips the hidden sequence, and can rewrite the wording too.
It dependsMicrosoft has announced no watermark in the wording of Copilot text. Its Windows AI text APIs hide four invisible characters, which stripping removes completely. Rewrite only if you know a Claude model wrote it: those carry Claude’s watermark.
▸Hidden-character optionscore invisibles, tags & private-use are always removed
Facts checked against the sources below on .
Does Microsoft Copilot watermark its text?
Microsoft 365 Copilot’s watermark documentation covers images, audio and video, not text. On Azure, Microsoft Foundry lets customers switch on a watermark for selected OpenAI model deployments, and Claude models offered through Foundry carry Anthropic’s own watermark, according to Anthropic.
Where Copilot features run on Anthropic’s Claude models, Anthropic says its supported models are watermarked wherever they are offered — but Microsoft hasn’t said which Copilot text, if any, carries that mark.
The Windows AI text watermark
The one Microsoft text watermark that is documented in detail is made of characters. Since October 2026, the Microsoft.Windows.AI.Text APIs — the on-device Phi Silica generate, rewrite and summarise calls — insert U+200B U+034F U+2060 U+200B (zero-width space, combining grapheme joiner, word joiner, zero-width space) zero, one or several times per response, in places that change between responses.
Because it is made of ordinary Unicode, it is fully detectable and fully removable: the AI watermark checker names the sequence and counts every copy, and Unmark strips them all with no rewrite needed. Developers can find code to handle it in our Windows AI text watermark guide.
How to clean Copilot text
Paste the text into the tool above. “Strip hidden chars only” removes the Windows AI sequence and any other invisible characters instantly, in your browser. “Remove watermark” also rewrites the wording, which is what removes a statistical watermark such as Claude’s, should the text carry one.