When I click the green plus icon in any window, I would like it to expand to the full size of my monitor, instead of having to drag the corner of the screen.
I have seen paid ($10+) tools that do this.
Is there some sort of Terminal hack or free program that would do it?
RightZoom is what you want (scroll down to the bottom of the page or use this MacUpdate link)
This free tool fixes an inconvenient behavior of green Zoom button in Mac OS X. It will always expand windows on a full screen instead of strange resizing.
Another one is BetterTouchTool. You might not think of BetterTouchTool as being a window manager, but it has window snapping (as seen in Windows 7). Take a look:
Cinch also does the same thing, but it costs $7.
In OS X Yosemite, just click the green plus (+) icon while holding Shift (⇧) + Option (⌥) keys.
Or double click on the window's title bar while holding Shift(⇧) key (this won't work if System Preferences > Dock > Double-click a window's title bar to minimize is checked).
UPDATE
Here are proofs for those who voted down my answer before even trying if it works:
If you Google for this, you’ll see lots of people recommending holding alt-shift before clicking the green button.
In order to maximize the window so that it fills the visible window content, use:
⌥ + Click on green icon
In order to maximize the window both in width and height to the current desktop for applications like Google Chrome use:
⌥ + ⇧ + Click on green icon
...by doing:
⌥ + ⇧ + Click on green or outer right icon (plus icon)
I can maximize a window in both width and height to the current screen.
I tried it and it works on my MacBook Pro 13" Retina with Mac OS X Yosemite.
SUMMARY
There is no need to buy or hack something to do the following things:
I use Spectacle it's free and open-source. A compiled version is available from the AppStore, versions for OS X 10.6 and 10.7 can be downloaded from the Spectacle GitHub site. You can change the various keyboard shortcuts that allow you to snap the window to any side or corner of the screen as well as maximize the application window to fit your screen.
The default shortcuts are:
Fullscreen / ⌘ + alt + F
Left Half / ⌘ + alt + ←
Bottom Half / ⌘+ alt + ↓
Upper Left Corner / ⌘ + control + ←
Lower Right Corner / ⌘+ shift + control + →
Left Display / ⌘ + alt + control + ←
I might have found a solution for Sierra and higher:
"Hold Option and double-click on any window corner."
Credits (which includes some other nice tricks): https://www.techradar.com/how-to/advanced-macos-sierra-windows-mangement-tips
I use Divvy for this sort of window management, it was the one that closest fit my mental model. It uses shortcuts to allow changing window size and position and it allows you to resize to a grid using the mouse very quickly.
You can define system wide shortcuts, or shortcuts which are only available when the Divvy window is open.
There are a lot of alternatives to Divvy, most are also commercial, but ShiftIt is free and open source, but with a more limited set of features.
What it does do is allow you to have a system wide shortcut for putting the window into a corner or vertical or horizontal halves or full screen.
The source is available on github, but if you aren't comfortable compiling the code yourself, or dont want to install the 4GB of Xcode needed to do so, I have uploaded my compiled version of ShiftIt to filedropper.com.
(All the usual warnings and none of the guarantees apply. I have not tested this code, apart from running it for a few days to try it out for personal use. Please be careful when downloading software from random people on the internet. Look both ways when crossing the road.)
Well, I'm using Snow Leopard and to my knowledge there is no way to trigger a fullscreen mode with just the click of a button. Unless something new has to come to light that I don't know of, you will simply have to drag the window and make it as large as you want by using the grabber on the bottom right of the screen.
Keep in mind, though, that it depends on the application. Some applications have a full screen mode.
To fully expand the window (both height and width): ⇧ Shift ⌥ Alt and click the green button on the top-left corner.
To maximize the window (only expand the height): pressing ⌥ Alt and click the green button on the top-left corner.
ShiftIt will do this, with its Maximize feature:
https://github.com/fikovnik/ShiftIt/issues/72#issuecomment-3727710
(The version 1.6 binary linked to from this page is more reliable than the default build from the default git hub page, and has an additional feature: it will move windows between monitors.)
In OSX Yosemite, you can achieve this by holding the ⌥ option and click the green (+).
I have used Moom for a long time with much satisfaction. It is a paid application. It expands the green icon to allow for various window arrangements, and can be customised. It also will swap windows between displays. I wish I'd known about these free options before, though.
On El Capitan on a 2015 Mac Book 13" screen I clicked on green icon top left - work page becomes a little bigger. Then at bottom left selected 150% Size. Almost full screen. Can now see it to work on it.
On 10.9.5, option-click on the green button in the top left.
