I got to think about code in my previous blog post about calculating the age of a given date in months and thought about a little more elegant way to do it, here is my modified version:

//Calculate the approximate age in months for a given date function getAgeInMonths(fromDateStr) { var frDate = new Date(fromDateStr); var toDate = new Date(); if (frDate > toDate) { throw "Given date is in future, invalid!"; } var frAge = (frDate.getFullYear() - 1) * 12 + frDate.getMonth() + 1; var toAge = (toDate.getFullYear() - 1) * 12 + toDate.getMonth() + 1; return toAge - frAge; } // test function to check some random dates function test_getAgeInMonths() { var arrDates = ['2011/05/01', '2010/09/05', '2002/02/25', '1980/03/23']; for (var i=0; i < arrDates.length; ++i) { var ln = 'getAgeInMonths("'+arrDates[i]+'") = ' + getAgeInMonths(arrDates[i]) + '<br/>'; document.writeln(ln); } }

I am basically calculating the age in months for each date since 0/0/0 AD and taking the difference between those ages. Here are the results from this version and they do match with the previous version:

Happy coding,

Sonny