Always show file extensions — via Apple Support

Hidden settinglow riskmacOS 14 Sonoma and later

By default Finder hides many file extensions, so 'report.pdf' and 'report.pdf.app' can look the same. Showing every extension tells you exactly what kind of file you're about to open, which is useful for security too.

Relaunch the app it changes (Finder, Dock…) to see it

The easy way

The easy way: in Finder choose Finder > Settings > Advanced and turn on Show all filename extensions.
Or in Terminal run the command below.

Command

Run in Terminal (Applications › Utilities).

defaults write NSGlobalDomain AppleShowAllExtensions -bool true; killall Finder

Undo

defaults delete NSGlobalDomain AppleShowAllExtensions; killall Finder

The same Advanced pane has Show warning before changing an extension. Turn it off if renaming extensions is part of your routine, but the warning helps stop you from renaming files by mistake.

Sources

Change Finder settings on Mac — by Apple Support
Show extensions — by Yann Bertrand, macos-defaults.com

Source reviewed: 2026-11-02
Link checked: 2026-11-02
Tested hands-on: Not by Oddbyte.Me

Oddbyte.Me hasn't tried this on every macOS version, so keep the undo handy.

file extensionsfinderfile typesAppleShowAllExtensions

Cut and paste files in Finder (move instead of copy) — via Apple Support

Tricklow risk

Finder has no Cut command in the Edit menu for files, which confuses people coming from Windows. There is a hidden equivalent: copy as normal, then paste with Option held down, and the file moves instead of being duplicated.

Keep folders above files when sorting by name — via Apple Support

Hidden settinglow risk

Normally Finder mixes folders and files together alphabetically. With this on, folders are listed first, then files, the way Windows Explorer does it. It can be set for windows and, separately, for the desktop.

Stop .DS_Store files on network shares (faster SMB browsing) — via Apple Support

Commandlow risk

Finder leaves .DS_Store files in every folder it opens to remember view settings, and on network shares reading them slows browsing. Apple documents a setting that stops this on SMB shares, so folders list faster. Windows and Linux users of the share will thank you too.

Always show file extensions — via Apple Support

The easy way

Command

Undo

Sources

More in Finder