cookie expires vs max-age

cookie.js

// http://mrcoles.com/blog/cookies-max-age-vs-expires/

var d = new Date();
d.setTime(d.getTime() + 5*60*1000); // in milliseconds
// -> 1427173295425
var gmt = d.toGMTString()
// -> gmt "Tue, 24 Mar 2015 05:01:35 GMT"
var restored = new Date(gmt
// -> restored Tue Mar 24 2015 06:01:35 GMT+0100 (CET)
var gmt2 = restored.toGMTString()

if (gmt == gmt2) console.log('recycled correctly');
// -> prints out: recycled correctly

document.cookie = 'foo=bar;path=/;expires='+d.toGMTString()+';';
// -> "foo=bar;path=/;expires=Tue, 24 Mar 2015 05:01:35 GMT;"
document.cookie = 'foo=bar;path=/;max-age='+5*60+';';
// -> "foo=bar;path=/;max-age=300;"

set-date.js

var date = new Date()
date.setSeconds(date.getSeconds() + (60*60*24))
// -> 1427260691127
date.toGMTString()
// -> "Wed, 25 Mar 2015 05:18:11 GMT"