You can use the setGridWidth property
$('#gridId').jqGrid('setGridWidth', '800');
If you want the grid to change dynamically, connect to the window resizing function, but do not forget to set the initial width
var DataGrid = $('#gridId'); //sets the grid size initially DataGrid.jqGrid('setGridWidth', parseInt($(window).width()) - 20); //handles the grid resize on window resize $(window).resize(function () { DataGrid.jqGrid('setGridWidth', parseInt($(window).width()) - 20); });
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