Fn+F does the job! It will maximize and minimize to a full-screen application.
Answer from Rob Kley on Stack ExchangeFn+F does the job! It will maximize and minimize to a full-screen application.
Using macOS 15.2 Sequoia here.
The menu item window->fill, defaults to ⌃F (Ctrl+Fn+f), should do what you want.
The item window->center ⌃C (Ctrl+Fn+c) restores the original size and centers the window.
Menu item window->minimize ⌘M (Cmd+m) minimizes the window.
To remove the spacing around the "filled" window, you have to go to System Settings -> "Desktop & Dock" -> disable the option "Tiled windows have margins"
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There's a BetterTouchTool app which does exactly what You need. You can download a trial and check it.

There's also Better Snap Tool from the same developer on the MacAppStore which does only window snapping.
Hold shift option ⌥ and click the green maximise button on the top left part of the window.

NOTE: not every OSX application is eligible for maximize (example: maximizing the Finder doesn't work)
Assign a shortcut for the Zoom menu item (or whatever it's called in your locale) from System Preferences:

If you want the shortcut to always maximize a window to fill a screen, you can use for example Spectacle:

Or add a line like this to ~/.slate with Slate:
bind m:cmd;shift move screenOriginX;screenOriginY screenSizeX;screenSizeY
I have used FastScripts to assign a shortcut to this script:
try
tell application "Finder" to set b to bounds of window of desktop
try
tell application (path to frontmost application as text)
set bounds of window 1 to {item 1 of b, 22, item 3 of b, item 4 of b}
end tell
on error
tell application "System Events" to tell window 1 of (process 1 where it is frontmost)
try
set position to {0, 22}
set size to {item 3 of b, (item 4 of b) - 22}
on error
click (button 1 of window 1 where subrole is "AXZoomButton")
end try
end tell
end try
end try
When you tell System Events to change the position and size through the accessibility API, there is a noticeable delay between when the position and the size are changed. Telling the application to change the bounds of a window is faster but it doesn't work with all applications. Other applications like Slate and Moom always use the accessiblity API.
Sorry I made a mistake about minimizing window. It's ready from Apple. So, I amended.
Answer:
- Command-M :Minimize the active window to the Dock
- Command-Option-M :Minimize all windows of the active application to the Dock
- (Setup is required) :Maximize the active window
To maximize the active window(application), you must assign the operation to shortcut key as follows;
- Go to System Preferences>Keyboard>Shortcuts>App Shortcut, then click "+" to add shortcut key.
- Choose "All Application" which means this change will affect all application, put the text "Maximize" in "Menu Title" textbox and press "Command+Shift+M" in "Shortcut Key" textbox.
- Restart Window(Application) which you would like to affect by the shortcut key.(No reboot requred)
- You will find new menu item in the menu bar also.
Recommendation basis:
I recommend you to use below shortcut key instead of using default minimizing shortcut key.
To Minimize the active window(application):
Command+H :Hide active window(application)
It's possible to minimize the active window in above shortcut key but actually it's hidden the active window(application). And, if you use this shortcut key, you can switch hidden window by shortcut key which is "Command + Tab" quickly. If you minimize the active window by Command+M, you can not switch application by command + Tab quickly and you have to click the application from Dock.)
You can refer related information in below.
http://support.apple.com/kb/HT1343, http://support.apple.com/kb/PH13911
Hi all. I’ve looked this up but can’t seem to find the solution.
I would like to have all my windows maximized when I open them, in any application on my Macbook (Monterrey). I don’t want to open them in full screen, but just want them to always open maximized. Can anyone help me out?
Hold down alt/option and double click in the corner (where you would drag to resize).
Is this something everybody but me knew all along?
On Yosemite:
- Double click the window top bar (Like in MS Windows)
or
- Option-click the green dot in the top left.
On older OS X versions: Shift-click the green (+)
Download and use RightZoom. It overrides your green plus (zoom) button and works like Windows maximize. You can add it to your login items in your user account to run every time you start OS X.