Mac Setup

Show all filename extensions

Show extensions such as .txt, .pdf, and .mov at the end of filenames so the file type is easier to identify.

Open the interactive guide

Finder

Settings path

Finder › Settings › Advanced › Show all filename extensions

Steps

  1. Open a Finder window.
  2. Look at the menu bar in the upper-left corner of the screen and confirm that “Finder” appears there.
  3. Click Finder in the menu bar, then click Settings.
  4. Click Advanced.
  5. Turn on “Show all filename extensions.”
  6. Return to a Finder window containing several file types and confirm that extensions such as .txt, .pdf, and .mov are visible.

Before

Finder may hide some filename extensions and show names such as “Setup Notes,” “Setup Guide,” or “Setup Demo.” The file type may not be clear from the name alone.

After

Finder shows full filenames such as “Setup Notes.txt,” “Setup Guide.pdf,” and “Setup Demo.mov,” making each format visible in the filename.

Undo the change

  • Open a Finder window, then click Finder > Settings > Advanced in the upper-left menu bar and turn off “Show all filename extensions.”

Sources and version notes

More settings