The Mac OS X Finder column view is really handy, letting you see multiple folder contents side by side in a hierarchical view. But unless you set the default column width yourself, anytime you launch a new Finder window, the columns size will be reset on a per window basis.

How to Set Default Column Size in Mac Finder

Changing the default column size behavior is very simple, and if you want to set the default column size for Column View in Finder of MacOS and Mac OS X, all you need to do is hover the mouse cursor over the column dividers of a Finder window, then hold down the Option key while dragging the columns to your desired width or size.

With the Option key modifier held as you resize, this will become the new default for Column Views in the Mac Finder.

If you’re tired of the Column view resizing itself or being reset on the Mac, this is the solution you’re looking for since it will lock as the default column width and column size.

This works in all versions of MacOS and Mac OS X that support Column View, and it’s an easy trick to remember even if it’s not the most obvious thing in the world. If you’re a column view user for Finder, try it out, you’ll find this to be quite useful.

And yes, you must be in Finder Column View to have this work, it does not work in the other Finder views since there is no divider to align and set the width of.

Note that the Option / ALT key trick is intended for most keyboards and a US keyboard set, but some users may find the Command key to work depending on their keyboard layout and keyboard country settings.

Another similar handy trick is to resize column view to fit file names, discussed here. If you’re working in Column view with long file names, it’s particularly handy.

Let us know in the comments what works for you, and share your experiences and tips if you have another approach to accomplish this task.