luxon

const luxon = require("luxon"); const int1 = luxon.Interval.fromDateTimes( luxon.DateTime.fromISO('2020-05-01T00:00:00'), luxon.DateTime.fromISO('2020-07-01T00:00:00'), ); const dur1 = int1.toDuration(); console.log(dur1.toFormat("M 'months'")); // "2 months"