Datatable Page Size Menu (lengthmenu)

Example

$('#example').dataTable( {
  "lengthMenu": [ 
    [10, 25, 50, -1], // value
    [10, 25, 50, "All"] // Display
  ]
});

$('#example').dataTable( {

"lengthMenu": [

[10, 25, 50, -1], // value

[10, 25, 50, "All"] // Display

]

});

Reference:

Rex's Personal Site