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I have a div with an id "main", I want to set its height using jQuery and making so that on window.resize its height is modified using a function but for some reason it works well only when increasing window's height, when decreasing it it doesn't work. This is the JS: function setMainH() { var docH = $(document).height(); $("#main").height(docH - 40); } $(function() { setMainH(); }); $(window).resize(function() { setMainH(); }); EDIT: the problem appears either increasing or decreasing EDIT 2: the resize() event seem to be called correctly, I've tried with console.log("resizing"); on resizing and it logs correctly so the problem isn't that.