How to get date different between two date in jquery?

get date different between two date in jquery:
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        var oneDay = 24 * 60 * 60 * 1000;
        var entryDate = kendo.parseDate(obj.RowDate, "d");
        var today = kendo.parseDate(new Date(), "d");
        var diffDays = Math.round(Math.abs((today.getTime() - entryDate.getTime()) / (oneDay)));