Age Calculator: How Old Am I? [Years, Months, Days]

To calculate your age, subtract your birth year from the current year, and subtract one more if your birthday hasn't come yet this year. Enter your date of birth above to get your exact age in years, months and days, plus total days, weeks and hours, your next birthday, star sign and Chinese zodiac.

How to use this calculator

Enter your date of birth.
Leave “Age on” as today, or change it to see how old you were, or will be, on another date.
Read your age in years, months and days.
Check the totals — months, weeks, days and hours — and the countdown to your next birthday.
Use the share button to send the result; the link keeps the dates you entered.

How it's calculated

Years and months: the calculator counts whole calendar months from your birth date to the “age on” date. Whole years = months ÷ 12; the rest are months.
Days: the days left after the last whole month. If your birth day doesn't exist in a month (the 31st, or 29 February), that month's anniversary falls on its last day.
Totals: total days is the exact day count between the two dates; weeks is days ÷ 7 and hours is days × 24.
Next birthday: your birth date plus your next age in years, with the same last-day-of-month rule.

This is the everyday “completed years” age used for most forms. It counts whole days, not the time of birth.

Worked examples (as of Sunday, October 11, 2026)

Born 31 May 1993

Age on Sunday, October 11, 2026: 33 years, 4 months and 11 days. That's 400 months, 1,740 weeks or 12,186 days in total. Born on a Monday, and in the Year of the Rooster.

Born 15 January 1987

On Sunday, October 11, 2026 the age is 39 — exactly 39 years, 8 months and 26 days. Because 15 January falls before Lunar New Year, the Chinese zodiac sign is the Tiger, not the animal for 1987.

Born 29 February 2000

Age on Sunday, October 11, 2026: 26 years, 7 months and 12 days. The next birthday is shown as Sunday, February 28, 2027, because this calculator uses 28 February in years without a 29th.

How to calculate age by hand

Subtract the birth year from this year. For someone born on 31 May 1993, 2026 − 1993 = 33.
If this year's birthday hasn't happened yet, subtract 1. That gives completed years.
Count whole months from the last birthday to today. If today's day of the month is smaller than the birth day, the current month isn't complete yet.
Count the remaining days from the last whole-month date to today.

Doing this by hand is where most errors creep in, because months have different lengths. The calculator does the same steps on the real calendar, so it handles 31st-of-the-month and leap-day birthdays consistently.

Age by birth year

If you only know the birth year, age is the current year minus the year, or one less if the birthday hasn't come yet this year. Someone born in 1993 is 33 after their 2026 birthday and 32 before it. The same subtraction gives “years ago”: 1970 was 56 years ago in 2026.

Age chart for birth years 1930–2015

Born in	Age in 2026 after birthday	Before birthday	Turns in 2027
2015	11	10	12
2014	12	11	13
2013	13	12	14
2012	14	13	15
2011	15	14	16
2010	16	15	17
2009	17	16	18
2008	18	17	19
2007	19	18	20
2006	20	19	21
2005	21	20	22
2004	22	21	23
2003	23	22	24
2002	24	23	25
2001	25	24	26
2000	26	25	27
1999	27	26	28
1998	28	27	29
1997	29	28	30
1996	30	29	31
1995	31	30	32
1994	32	31	33
1993	33	32	34
1992	34	33	35
1991	35	34	36
1990	36	35	37
1989	37	36	38
1988	38	37	39
1987	39	38	40
1986	40	39	41
1985	41	40	42
1984	42	41	43
1983	43	42	44
1982	44	43	45
1981	45	44	46
1980	46	45	47
1979	47	46	48
1978	48	47	49
1977	49	48	50
1976	50	49	51
1975	51	50	52
1974	52	51	53
1973	53	52	54
1972	54	53	55
1971	55	54	56
1970	56	55	57
1969	57	56	58
1968	58	57	59
1967	59	58	60
1966	60	59	61
1965	61	60	62
1964	62	61	63
1963	63	62	64
1962	64	63	65
1961	65	64	66
1960	66	65	67
1959	67	66	68
1958	68	67	69
1957	69	68	70
1956	70	69	71
1955	71	70	72
1954	72	71	73
1953	73	72	74
1952	74	73	75
1951	75	74	76
1950	76	75	77
1949	77	76	78
1948	78	77	79
1947	79	78	80
1946	80	79	81
1945	81	80	82
1944	82	81	83
1943	83	82	84
1942	84	83	85
1941	85	84	86
1940	86	85	87
1939	87	86	88
1938	88	87	89
1937	89	88	90
1936	90	89	91
1935	91	90	92
1934	92	91	93
1933	93	92	94
1932	94	93	95
1931	95	94	96
1930	96	95	97

Half birthdays

Your half birthday is your birth date plus six months — the day you turn X½. The calculator above shows your next half birthday and how many days away it is. If the six-months-later date doesn't exist, it falls on the last day of that month: a 31 August birthday gives a half birthday on 28 February (29 February in a leap year), and a 31 May birthday gives 30 November.

Example: born Monday, May 31, 1993, the next half birthday after Sunday, October 11, 2026 is Monday, November 30, 2026. A half birthday is an informal custom, not a legal date.

Chronological and corrected age

Washington State's Department of Children, Youth & Families defines chronological age as the “time elapsed since birth, measured in years, months and days” — also called actual age. That's exactly what this calculator gives: put the birth date in “Date of birth” and the test date in “Age on”.

For babies born before 37 weeks, the same guidance uses corrected age: chronological age minus (40 weeks − gestational age at birth). A 16-month-old born at 28 weeks is 16 − 3 = 13 months corrected. DCYF stops correcting once a child reaches 24 months chronological age.

Birth dates for a given age today

Working backwards — for an age check, a form or a birthday-date question — this table gives the birth dates that make someone exactly that age today. As of Sunday, October 11, 2026, a 21-year-old was born between October 12, 2004 and October 11, 2005.

Age today	Born between	At least this age if born on or before
16	October 12, 2009 – October 11, 2010	October 11, 2010
18	October 12, 2007 – October 11, 2008	October 11, 2008
19	October 12, 2006 – October 11, 2007	October 11, 2007
21	October 12, 2004 – October 11, 2005	October 11, 2005
25	October 12, 2000 – October 11, 2001	October 11, 2001
30	October 12, 1995 – October 11, 1996	October 11, 1996
35	October 12, 1990 – October 11, 1991	October 11, 1991
40	October 12, 1985 – October 11, 1986	October 11, 1986
50	October 12, 1975 – October 11, 1976	October 11, 1976
55	October 12, 1970 – October 11, 1971	October 11, 1971
60	October 12, 1965 – October 11, 1966	October 11, 1966
62	October 12, 1963 – October 11, 1964	October 11, 1964
65	October 12, 1960 – October 11, 1961	October 11, 1961
67	October 12, 1958 – October 11, 1959	October 11, 1959

Age in days: milestone birthdays

Some people mark 10,000 days (about 27 years 4 months) as a milestone. This table shows when each round number falls for someone born on Monday, May 31, 1993; enter your own birth date above for your total.

Days old	Date	Age then
1,000	Sunday, February 25, 1996	2 y 8 m 25 d
5,000	Wednesday, February 7, 2007	13 y 8 m 7 d
10,000	Friday, October 16, 2020	27 y 4 m 16 d
15,000	Sunday, June 25, 2034	41 y 0 m 25 d
20,000	Tuesday, March 3, 2048	54 y 9 m 3 d
25,000	Thursday, November 10, 2061	68 y 5 m 10 d
30,000	Saturday, July 20, 2075	82 y 1 m 20 d

Leap-year birthdays and legal age

If you were born on 29 February, your birthday only appears on the calendar in leap years. Most of the time this doesn't matter, but it can when a legal age starts on a set day. The rules differ:

Scotland — in a common year you reach the age on 1 March (Age of Legal Capacity (Scotland) Act 1991, s.6).
Hong Kong — also 1 March (Age of Majority (Related Provisions) Ordinance, Cap. 410, s.5).
England & Wales — you attain an age at the start of the relevant anniversary of your birth date (Family Law Reform Act 1969, s.9), with no specific leap-day rule.

This calculator uses 28 February, the common everyday convention. If a legal right, benefit or deadline depends on your exact age, check the rule where you live — this page is not legal advice.

Common mistakes

Subtracting years only. 2026 − 1993 = 33, but anyone born later in the year than today is still 32.
Counting months as 30 days. Months are 28 to 31 days long, so “days” in an age depends on which months you cross. The calculator uses the real calendar.
Chinese zodiac by year only. If you were born before Lunar New Year, your animal is the previous year's.
Star-sign cusps. Sources differ by a day at the edges of signs, partly because the equinox and solstice dates shift slightly year to year.

To check eligibility by date of birth, try the NDA age calculator; to count days, weeks and months between any two dates, use the days from today calculator.

Frequently asked questions

How old am I if I was born in 1993?

In 2026 you are 33 if your birthday has passed this year, or 32 if it hasn't yet. The rule for any year: current year minus birth year, minus one more before your birthday. The birth-year chart on this page lists both ages for every year from 1930, and the same subtraction tells you how many years ago a year was (1970 was 56 years ago).

How many days old am I?

Count the days from your date of birth to today; the calculator shows this as total days. Someone born on Monday, May 31, 1993 was 12,186 days old on Sunday, October 11, 2026. Because this counts calendar days, it includes every leap day you've lived through, which is why it can't be found by multiplying your age by 365.

How is age calculated for a February 29 birthday?

In non-leap years this calculator counts the birthday on 28 February. The law varies by place: Scotland and Hong Kong set it by statute as 1 March, while England & Wales say only that you reach an age at the start of the anniversary of your birth date, without a leap-day rule. Leap years follow the Gregorian rule — divisible by 4, except century years not divisible by 400, so 2100 will not have a 29 February (U.S. Naval Observatory). If a legal age matters, check the rule where you live.

What is the date of birth for someone who is 21 today?

On Sunday, October 11, 2026, anyone born between October 12, 2004 and October 11, 2005 is 21. To be at least 21 today you must have been born on or before October 11, 2005; for 18 the cut-off is October 11, 2008. Anyone born a day earlier than the range has already turned 22.

How do you calculate chronological age?

Chronological age is the time elapsed since birth, in years, months and days (Washington State DCYF). Subtract the birth date from the test or reference date: whole years, then whole months, then leftover days. Enter the test date in 'Age on' and the calculator gives it exactly. For babies born preterm, assessments may use corrected age instead — see the section below.

How do I find out how old someone was on a past date?

Change the 'Age on' date to that day. The calculator then shows their age in years, months and days on that date instead of today — useful for historical records, or for the age someone was when an event happened.

What is a half birthday and how do I calculate it?

A half birthday is six months after your birthday — the point where you are exactly X½ years old. Add six months to your birth date: born 31 May, your half birthday is 30 November (November has no 31st). For someone born on Monday, May 31, 1993 the next one is Monday, November 30, 2026.

What is my Chinese zodiac sign?

It depends on your birth date, not only the year, because the Chinese zodiac year starts at Lunar New Year, between 21 January and 20 February (Hong Kong Observatory). If you were born in January or early February, you may belong to the previous year's animal. The calculator checks this for you.

Sources & method

Results are estimates for general information. Found an error? It helps everyone — see our methodology.

Age Calculator – How Old Am I?