Settings – Files

The Files tab controls what BetterZip does with individual file types that live inside archives: which app opens them on double-click, where they get extracted to, and how the preview pane renders them. The available preview modes are Default, Text, Image, PDF, and Quick Look.

The File Types Table

Each row is one file type, identified by its Extensions pattern (the second column). The columns show:

• Extensions: a regular expression matched against the file’s extension. In the simplest case, just type the extension (jpg). Several extensions go together with vertical bars: jpg|jpeg|png. Anything regex can express works too, e.g. [0-9]+ to catch all numeric extensions.
• Double Click Action: what happens when you double-click a file of this type inside an archive: Open in an external app, Extract to a given destination folder, or Ignore.
• Application or Path (depending on the action above): the app to open the file in, or the destination folder. Leave empty to use the system default. You can drop an app or folder onto the cell or type a path.
• Preview: how the preview pane should render this file: as text, image, PDF, web content, or via the system’s Quick Look.

Add a new file type with the + button and fill in the extensions pattern. Remove one with –. Rows are matched top-to-bottom: the first regex that matches the file’s extension wins.

Known and Unknown File Types

Two special rows are pinned to the bottom of the table. They catch every file extension that none of the rows above match, but they split that pool by whether macOS knows what to do with the file:

• Known file types: macOS has a default application registered for the extension (any app declared a handler for it, even if the file itself doesn’t live on disk). The rule’s settings decide what BetterZip does with such files: typically Open hands the file to the macOS default app, and Extract puts a copy somewhere predictable first.
• Unknown file types: macOS has no registered handler for the extension. Without this fallback, double-clicking such a file would do nothing useful. Point the rule at a generic viewer (e.g., a hex editor, BBEdit, Path Finder) and BetterZip will route every otherwise-unknown file through it.

The two rules can’t be deleted or renamed; their extensions column shows the localized labels instead of a pattern. Edit them like any other row to change the action, app, or preview behavior.

Defaults vs. Overrides

BetterZip ships with sensible defaults for common types: images preview as images, text files preview as text, source code opens in your default editor on double-click, and so on. The tab lets you override any of these and add new types.