The main file extension for Microsoft Word documents is .docx in modern versions, and .doc in older versions.

Quick Scoop: Short Answer

  • For recent Microsoft Word (Word 2007 and later), the default extension of a Word file is .docx.
  • In older versions (Word 97–2003), the typical extension was .doc.

Mini Breakdown: Common Word Extensions

  • .docx – Standard editable Word document in current versions, based on the Office Open XML format.
  • .doc – Legacy Word document format used before Word 2007, still recognized by modern Word.
  • .dotx – Word template file without macros (used as a base to create many similar documents).
  • .dotm – Word template that can contain macros.
  • .dot – Older (pre-2007) Word template format.

If someone casually asks, “What is the extension of Word file?”, they almost always mean .docx today, unless they are specifically talking about very old Word versions.

Meta note (SEO-style):
People searching for “what is the extension of word file” today are usually looking for .docx as the primary answer, with .doc as the older variant still seen in shared files or legacy systems.

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