Moment.js - how do I get the number of years since a date, not rounded up?

Question

I'm trying to calculate a person's age using Moment.js, but I'm finding that the otherwise useful fromNow method rounds up the years. For instance, if today is 12/27/2012 and the person's birth date is 02/26/1978, moment("02/26/1978", "MM/DD/YYYY").fromNow() returns '35 years ago'. How can I make Moment.js ignore the number of months, and simply return the number of years (i.e. 34) since the date?

Answer 1

I found that it would work to reset the month to January for both dates (the provided date and the present):

> moment("02/26/1978", "MM/DD/YYYY").month(0).from(moment().month(0))
"34 years ago"

Answer 2

Using moment.js is as easy as:

var years = moment().diff('1981-01-01', 'years');
var days = moment().diff('1981-01-01', 'days');

For additional reference, you can read moment.js official documentation.

Answer 3

http://jsfiddle.net/xR8t5/27/

if you do not want fraction values:

var years = moment().diff('1981-01-01', 'years',false);
alert( years);

if you want fraction values:

var years = moment().diff('1981-01-01', 'years',true);
alert( years);

Units can be [seconds, minutes, hours, days, weeks, months, years]

Answer 4

There appears to be a difference function that accepts time intervals to use as well as an option to not round the result. So, something like

Math.floor(moment(new Date()).diff(moment("02/26/1978","MM/DD/YYYY"),'years',true)))

I haven't tried this, and I'm not completely familiar with moment, but it seems like this should get what you want (without having to reset the month).

Answer 5

This method is easy and powerful.

Value is a date and "DD-MM-YYYY" is the mask of the date.

moment().diff(moment(value, "DD-MM-YYYY"), 'years');

Answer 6

Try this:

 moment("02/26/1978", "MM/DD/YYYY").fromNow().split(" ")[0];

Explanation:

We receive string something like this: '23 days ago'. Split it to array: ['23', 'days', 'ago'] and then take first item '23'.

Answer 7

This method works for me. It's checking if the person has had their birthday this year and subtracts one year otherwise.

// date is the moment you're calculating the age of
var now = moment().unix();
var then = date.unix();
var diff = (now - then) / (60 * 60 * 24 * 365);
var years = Math.floor(diff);

Edit: First version didn't quite work perfectly. The updated one should

Answer 8

If you dont want to use any module for age calculation

var age = Math.floor((new Date() - new Date(date_of_birth)) / 1000 / 60 / 60 / 24 / 365.25)

Answer 9

When you want to show years and the remaining days:

var m = moment(d.birthday.date, "DD.MM.YYYY");
var years = moment().diff(m, 'years', false);
var days = moment().diff(m.add(years, 'years'), 'days', false);
alert(years + ' years, ' + days + ' days');

Answer 10

I prefer this small method.

function getAgeFromBirthday(birthday) {
    if(birthday){
      var totalMonths = moment().diff(birthday, 'months');
      var years = parseInt(totalMonths / 12);
      var months = totalMonths % 12;
        if(months !== 0){
           return parseFloat(years + '.' + months);
         }
    return years;
      }
    return null;
}

Answer 11

Get years and days using moment.js library

import moment from 'moment'

export function getAge(dateString: string) {
  const date = moment(dateString, 'YYYY-MM-DD')
  const years = moment().diff(date, 'years')
  const days = moment().diff(date.add(years, 'years'), 'days', false)
  return { years, days }
}

const birthDate = "1997-04-01T00:00:00.000Z";
const age = getAge(birthDate);

// Today is 2022-04-09
console.log({ age })
// Result: { age: { years: 25, days: 8 } }

Answer 12

Here is the simple one using moment.js

let dt = dob;

        let age = '';

        let bY = Number(moment(dt).format('YYYY')); 
        let bM = Number(moment(dt).format('MM')); 
        let bD = Number(moment(dt).format('DD')); 

        let tY = Number(moment().format('YYYY')); 
        let tM = Number(moment().format('MM')); 
        let tD = Number(moment().format('DD')); 


        age += (tY - bY) + ' Y ';

        if (tM < bM) {
            age += (tM - bM + 12) + ' M ';
            tY = tY - 1;
        } else {
            age += (tM - bM) + ' M '
        }

        if (tD < bD) {
            age += (tD - bD + 30) + ' D ';
            tM = tM - 1;
        } else {
            age += (tD - bD) + ' D '
        }
        
        //AGE MONTH DAYS
        console.log(age);