Short answer
What you need to know
Turn on formatting marks and hidden-text display, review tracked changes and comments, inspect headers, footers, text boxes, and properties, then use Word's Document Inspector on a copy. No single view exposes every hidden element.
Where Word retains concealed content
DOCX files can contain hidden formatting, white or tiny text, comments, unresolved revisions, headers, footers, text boxes, alternate text, custom properties, relationships, and embedded files.
Much of this can be ordinary editing residue. Context matters more than one signal.
Inspect a copy in Microsoft Word
Preserve the original, then enable formatting marks and hidden-text display.
Open the Reviewing pane, show all markup, and examine comments, insertions, deletions, headers, footers, notes, text boxes, shapes, links, and properties.
Run File > Info > Check for Issues > Inspect Document on the duplicate. Review each category before removing anything.
What Hidden Word Scanner checks
The scanner examines the DOCX package for hidden formatting, unusual size or color, comments, revisions, headers, footers, text boxes, alternate text, properties, external relationships, and embedded objects without modifying the file.
Important limitation
Verify important findings
Legacy DOC files, encrypted documents, macros, extensions, and externally rendered objects may need separate tools. Automated findings do not establish why content is present.
Further reading
Authoritative references
These primary sources support the manual steps in this guide. Their inclusion does not imply endorsement of Hidden Word Scanner.