Guides

Plain answers about what files carry without showing it, and how to remove what you don't want to share. 12 guides, checked every month.

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What hidden data is in a file?

Most files carry hidden data. Text can contain invisible characters and hidden messages. Photos usually store the GPS location, camera and time. AI images can hold Content Credentials, AI labels and the prompt used. Word and PDF files keep author names, edit history, comments and sometimes deleted text.

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Text and copied writing

Invisible characters, AI text watermarks, and why pasted text misbehaves.

3 min readKey guideDoes ChatGPT watermark text?What OpenAI and Google actually do to mark AI text in 2026, and what the "hidden character" claims get wrong.Read the guide3 min readKey guideDoes Claude watermark text?How Anthropic's Claude watermark works, what it covers, who can detect it, and its limits.Read the guide2 min readWhy copied text breaks formattingThe invisible characters behind broken searches, failed passwords and odd spacing in pasted text.Read the guide

Tools for thisInvisible character checkerChatGPT text cleaner

AI images and video

Content Credentials, SynthID, and how to tell what was made with AI.

3 min readKey guideHow to tell if an image is AI-generatedFive checks, from the file's own labels to watermarks and reverse search, in the order that works.Read the guide2 min readSynthID explainedWhat Google's invisible AI watermark is, where it's used, how to check for it, and its limits.Read the guide2 min readWhat's inside ChatGPT and Gemini imagesThe Content Credentials, AI labels and watermarks that ChatGPT, Gemini and Firefly put in their images.Read the guide

Tools for thisAI image checkerContent Credentials checkerAI video checker

Photos and location

What your photos reveal about where you were, and how to share them safely.

2 min readKey guideRemove location from photos on iPhoneTurn off location when sharing, remove it from saved photos, and stop the Camera recording it.Read the guide2 min readRemove location from photos on AndroidSamsung Gallery, Google Photos and camera settings, step by step.Read the guide2 min readKey guideWhich apps remove photo metadata?WhatsApp, Signal, Telegram, iMessage, Instagram, email and cloud links compared.Read the guide

Tools for thisEXIF viewerPhoto metadata remover

Word and PDF files

Author names, comments and leftover text in the documents you send.

2 min readRemove metadata from Word documentsUse Document Inspector to strip author names, comments, tracked changes and hidden text.Read the guide2 min readRemove metadata from PDFsClear author and software details, hidden content and leftover text with Acrobat or free tools.Read the guide

Tools for thisWord and PDF metadata viewer

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