open

opens files and URLs on macOS

Open file with default app

$ open [file]

Open URL in browser

$ open [https://example.com]

Open with specific app

$ open -a [Safari] [file.html]

Open directory in Finder

$ open [directory]

Open current directory

$ open .

Reveal in Finder

$ open -R [file]

open [options] [file...]

open opens files and URLs on macOS. Uses default or specified applications.
The command launches applications with files. macOS specific utility.

FILE

File or URL to open.

-a APP

Open with application.

-e

Open in TextEdit.

-t

Open in default text editor.

-R

Reveal in Finder.

-n

Open new instance.

--help

Display help information.

macOS specific. Use xdg-open on Linux. Application names case-sensitive.

open has been part of macOS for launching files with associated applications.