Windows: can be used on Windows systems but is only available through various ports (such as Cygwin).
Based on https://gist.github.com/arunoda/7790979#file-gistfile1-md and http://stackoverflow.com/questions/37243087/how-to-install-sshpass-on-windows-through-cygwin
apt-get install sshpass
Installing on OS X is tricky, since there is no official build for it. Before you get started, you need install xcode and command line tools.
Installing with Homebrew
Homebrew does not allow you to install sshpass by default. But you can use the following unofficial brew package for that:
brew install https://raw.githubusercontent.com/kadwanev/bigboybrew/master/Library/Formula/sshpass.rb
Installing from the Source
Download the Source Code
Extract it and cd into the directory
sudo make install
Sshpass is not available as cygwin package. This means that you need to build and install from source. See for reference on existing alternative: https://www.cygwin.com/ml/cygwin/2015-02/msg00042.html