How to calculate the age based on NSDate
Solution 1
Many of these answers don't properly account for leap years and such, best is to use Apple's methods instead of dividing by constants.
Swift
let birthday: NSDate = ...
let now = Date()
let ageComponents = calendar.dateComponents([.year], from: birthday, to: now)
let age = ageComponents.year
Objective-C
NSDate* birthday = ...;
NSDate* now = [NSDate date];
NSDateComponents* ageComponents = [[NSCalendar currentCalendar]
components:NSCalendarUnitYear
fromDate:birthday
toDate:now
options:0];
NSInteger age = [ageComponents year];
I think this is cleaner and more accurate than any of the other answers here.
Edit
Increase accuracy by setting both birthday
and now
to noon. Here is one way to do that with a Date
extension (in Swift)...
/// Returns a new date identical to the receiver except set to precisely noon.
/// Example: let now = Date().atNoon()
func atNoon() -> Date {
var components = (Calendar.current as NSCalendar).components([.day, .month, .year, .era, .calendar, .timeZone], from: self)
components.hour = 12
components.minute = 0
components.second = 0
components.nanosecond = 0
return Calendar.current.date(from: components)!
}
Solution 2
Here's how you can calculate your actual age based on your birth date in years and days:
NSString *birthDate = @"03/31/1990";
NSDate *todayDate = [NSDate date];
NSDateFormatter *dateFormatter = [[NSDateFormatter alloc] init];
[dateFormatter setDateFormat:@"MM/dd/yyyy"];
int time = [todayDate timeIntervalSinceDate:[dateFormatter dateFromString:birthDate]];
int allDays = (((time/60)/60)/24);
int days = allDays%365;
int years = (allDays-days)/365;
NSLog(@"You live since %i years and %i days",years,days);
It returns the years and the exact days. And if you need you can change the NSDateFormatter and much more.
Solution 3
This is the code I got from this link.. it works great.. Out put will be like "5 years 6 months" and all usecases are covered in it.
- (NSString *)age:(NSDate *)dateOfBirth {
NSInteger years;
NSInteger months;
NSInteger days;
NSCalendar *calendar = [NSCalendar currentCalendar];
unsigned unitFlags = NSCalendarUnitYear | NSCalendarUnitMonth | NSCalendarUnitDay;
NSDateComponents *dateComponentsNow = [calendar components:unitFlags fromDate:[NSDate date]];
NSDateComponents *dateComponentsBirth = [calendar components:unitFlags fromDate:dateOfBirth];
if (([dateComponentsNow month] < [dateComponentsBirth month]) ||
(([dateComponentsNow month] == [dateComponentsBirth month]) && ([dateComponentsNow day] < [dateComponentsBirth day]))) {
years = [dateComponentsNow year] - [dateComponentsBirth year] - 1;
} else {
years = [dateComponentsNow year] - [dateComponentsBirth year];
}
if ([dateComponentsNow year] == [dateComponentsBirth year]) {
months = [dateComponentsNow month] - [dateComponentsBirth month];
} else if ([dateComponentsNow year] > [dateComponentsBirth year] && [dateComponentsNow month] > [dateComponentsBirth month]) {
months = [dateComponentsNow month] - [dateComponentsBirth month];
} else if ([dateComponentsNow year] > [dateComponentsBirth year] && [dateComponentsNow month] < [dateComponentsBirth month]) {
months = [dateComponentsNow month] - [dateComponentsBirth month] + 12;
} else {
months = [dateComponentsNow month] - [dateComponentsBirth month];
}
if ([dateComponentsNow year] == [dateComponentsBirth year] && [dateComponentsNow month] == [dateComponentsBirth month]) {
days = [dateComponentsNow day] - [dateComponentsBirth day];
}
if (years == 0 && months == 0) {
if (days == 1) {
return [NSString stringWithFormat:@"%d day", days];
} else {
return [NSString stringWithFormat:@"%d days", days];
}
} else if (years == 0) {
if (months == 1) {
return [NSString stringWithFormat:@"%d month", months];
} else {
return [NSString stringWithFormat:@"%d months", months];
}
} else if ((years != 0) && (months == 0)) {
if (years == 1) {
return [NSString stringWithFormat:@"%d year", years];
} else {
return [NSString stringWithFormat:@"%d years", years];
}
} else {
if ((years == 1) && (months == 1)) {
return [NSString stringWithFormat:@"%d year and %d month", years, months];
} else if (years == 1) {
return [NSString stringWithFormat:@"%d year and %d months", years, months];
} else if (months == 1) {
return [NSString stringWithFormat:@"%d years and %d month", years, months];
} else {
return [NSString stringWithFormat:@"%d years and %d months", years, months];
}
}
}
If you want age as int try the following answer.. which I got from following link
- (NSInteger)age:(NSDate *)dateOfBirth {
NSCalendar *calendar = [NSCalendar currentCalendar];
unsigned unitFlags = NSCalendarUnitYear | NSCalendarUnitMonth | NSCalendarUnitDay;
NSDateComponents *dateComponentsNow = [calendar components:unitFlags fromDate:[NSDate date]];
NSDateComponents *dateComponentsBirth = [calendar components:unitFlags fromDate:dateOfBirth];
if (([dateComponentsNow month] < [dateComponentsBirth month]) ||
(([dateComponentsNow month] == [dateComponentsBirth month]) && ([dateComponentsNow day] < [dateComponentsBirth day]))) {
return [dateComponentsNow year] - [dateComponentsBirth year] - 1;
} else {
return [dateComponentsNow year] - [dateComponentsBirth year];
}
}
Hope this helps some one..
Solution 4
A simple to use swift extension to get the age/how old is a NSDate
extension NSDate {
var age: Int {
let calendar: NSCalendar = NSCalendar.currentCalendar()
let now = calendar.startOfDayForDate(NSDate())
let birthdate = calendar.startOfDayForDate(self)
let components = calendar.components(.Year, fromDate: birthdate, toDate: now, options: [])
return components.year
}
}
Exemple:
NSDate(timeIntervalSince1970:0).age // => 45 (as of nov 2015) Epoch happened 45 year ago !
By the way, you should be careful, this is the western conception of age, the counting is different in some other countries (Korea for exemple).
Solution 5
If u want to find age alone .use below one which include leap year calculation too
- (NSInteger)age:(NSDate *)dateOfBirth {
NSCalendar *calendar = [NSCalendar currentCalendar];
unsigned unitFlags = NSYearCalendarUnit | NSMonthCalendarUnit | NSDayCalendarUnit;
NSDateComponents *dateComponentsNow = [calendar components:unitFlags fromDate:[NSDate date]];
NSDateComponents *dateComponentsBirth = [calendar components:unitFlags fromDate:dateOfBirth];
if (([dateComponentsNow month] < [dateComponentsBirth month]) ||
(([dateComponentsNow month] == [dateComponentsBirth month]) && ([dateComponentsNow day] < [dateComponentsBirth day]))) {
return [dateComponentsNow year] - [dateComponentsBirth year] - 1;
} else {
return [dateComponentsNow year] - [dateComponentsBirth year];
}
}

Linux world
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Updated on July 09, 2022Comments
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Linux world 6 months
how to calculate the age based on the birth date in this format 6/24/1976 mon/date/year...
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Daniel Rinser over 10 yearsAnd there are no leap years where you live? ;)
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Fabio Poloni over 10 yearsI live on Mars - Curiosity just hasn't discovered me yet. I'm not familiar with the possibilities of date-calculations in Objective-C, but my answer is a quite simple solution, but I think there's a more exact solution out there (on your planet) ;-)
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Razvan about 10 yearsWow ! Great answer ! This deserves a self Face Palm :D !
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Francis F about 9 yearsThat helped me to get the age as int. In my case I also had to convert the date from string before calling the function NSDateFormatter *dateFormat = [[NSDateFormatter alloc] init]; [dateFormat setDateFormat:@"MM/dd/yyyy"]; NSDate *dob = [dateFormat dateFromString:@"11/19/1986"]; NSLog(@"AGE:%d",[self age:dob]);
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Francis F about 9 yearsThat helped me to get the age as int. In my case I also had to convert the date from string before using this: NSDateFormatter *dateFormat = [[NSDateFormatter alloc] init]; [dateFormat setDateFormat:@"MM/dd/yyyy"]; NSDate *birthday = [dateFormat dateFromString:@"11/19/1986"];
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Johnny almost 9 yearswhat if it is a leap year?
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Pedro over 8 yearsIt's simpler, not accurate :-)
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vishal dharankar over 8 yearsmost complete answer calculates months as well , thanks
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cmario about 7 yearsofc I have to add this should be the correct answer
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Yoko almost 7 yearsGreat job, been using this ever since your answer! Thx!
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Murray Sagal over 6 yearsI made a bunch of test cases for this and ran into an edge case where a birthday of a year ago, for example, was returning zero. It seemed the time components were different enough to throw it off. I tried all the different option parameters but they didn't correct it. In the end I set
now
andbirthday
both to noon and that fixed it. -
Luke Irvin about 5 yearsHow would you calculate months using this approach?
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matt almost 3 years@MurraySagal This should be edited into the answer! It is crucial that
now
andbirthday
start at the same time, because of the quirk in the way we humans calculate age: it is your birthday all day no matter what time you were actually born at.