Birthday Calculator
Discover your age, the day you were born, days until your next birthday, and your zodiac sign.
Did this tool work for you?
How to use this calculator
- 1
Pick the birth date in the date field; the tool opens on 1990-06-15 until you change it.
- 2
Read the age as years, months and days, measured to the date on your device.
- 3
Check the weekday of birth and the days remaining until the next birthday, with the year it falls in.
- 4
Use the total-days figure and the Western sun sign for the remaining facts; a future or empty date returns a message or a dash instead.
Frequently asked questions
What does the calculator use as today’s date?
Your device’s local date. There is no field for a different reference date. To see someone’s age on a specific day, such as an exam date, use the age calculator, which has an “Age as of” field.
How are zodiac signs decided?
By fixed month-and-day ranges for the Western sun sign, with the year ignored. For example 21 March to 19 April is Aries and 20 March is Pisces. Published tables can differ by a day at the edges, and the tool does not use the birth time or place, so someone born on a cusp day should not treat the result as definitive.
What does “Next birthday in” show on the birthday itself?
The words “Today!” and the current year, once the person is at least one year old. The day after, the count jumps to 364 or 365 and the year moves forward by one. A person born today has an age of 0, so the first birthday is a full year away and the line shows 365 days.
What about a birthday on February 29?
In years without a leap day the birthday is placed on February 28. For a 2000-02-29 birth, the next birthday after November 3, 2026 is February 28, 2027, 117 days later, and the age comes out as 26 years, 8 months, 5 days. In a leap year the birthday is the true February 29.
How is the day of the week of birth found?
The date is converted to a weekday using the standard Gregorian calendar. 1990-06-15 was a Friday and 2000-02-29 a Tuesday. For dates before the Gregorian calendar was adopted locally, the weekday shown is the proleptic one, not what people then would have recorded.
What does “Total days lived” include?
The number of days elapsed since the birth date, with the day of birth counted as zero. For a 1990-06-15 birth it is 13,290 days as of 2026-11-03.
What if the birth date is in the future?
The tool replies that the date is in the future and shows no age. An empty or unreadable date returns a dash.
Birthday calculator — age, birth weekday, zodiac sign and next-birthday countdown
What you get from one date
Enter a birth date and the calculator returns six things: exact age in years, months and days, the weekday you were born, days until the next birthday and which year that falls in, total days lived, and the Western sun sign. All of them are measured against your device’s current date, so the numbers change from day to day and are worth recomputing near the day itself. The weekday of birth never changes, and neither does the sign.
Worked examples
The rows below were produced with the device clock mocked to November 3, 2026, so the age, weekday, countdown to the next birthday and zodiac sign each come from the same fixed day. A real visit on any other date shifts every figure except the weekday and the sign. Total days lived for the first row is 13,290 and for the 2000-02-29 row 9,744.
| Born | Age | Weekday | Next birthday | Sign |
|---|---|---|---|---|
| 1990-06-15 | 36 yrs, 4 mo, 19 days | Friday | 224 days (2027) | Gemini |
| 1988-11-03 | 38 yrs, 0 mo, 0 days | Thursday | Today (2026) | Scorpio |
| 1990-11-04 | 35 yrs, 11 mo, 30 days | Sunday | 1 day (2026) | Scorpio |
| 1990-12-25 | 35 yrs, 10 mo, 9 days | Tuesday | 52 days (2026) | Capricorn |
| 2000-02-29 | 26 yrs, 8 mo, 5 days | Tuesday | 117 days (2027) | Pisces |
The zodiac cut-off dates the tool uses
Signs follow fixed calendar ranges: Aries 21 March–19 April, Taurus 20 April–20 May, Gemini 21 May–20 June, Cancer 21 June–22 July, Leo 23 July–22 August, Virgo 23 August–22 September, Libra 23 September–22 October, Scorpio 23 October–21 November, Sagittarius 22 November–21 December, Capricorn 22 December–19 January, Aquarius 20 January–18 February, Pisces 19 February–20 March. Born on 21 March 1995 the tool says Aries; one day earlier it says Pisces. Real cusp dates move slightly from year to year, so treat the edges as approximate.
What the tool shows on the birthday itself
When the date matches the birthday, the countdown reads “Today!” and the next-birthday year stays at the current year, which is why the 1988-11-03 row shows an age of exactly 38 years, 0 months and 0 days alongside it. One day later the countdown restarts at 364 or 365. Leap-day births follow the same rule: with the clock set to 2027-02-28, a 2000-02-29 birth shows an age of exactly 27 years and “Today!”, and with the clock set to 2028-02-29 it shows 28 years and “Today!” again.
When to use the age calculator instead
This page always measures to today. To find an age on a past or future date, such as a school cutoff or a policy start, use the age calculator, which accepts a reference date and uses the same year, month and day arithmetic. The two tools agree on any given day, so you can check one against the other.
Learn more from an authoritative source:
WikipediaRetirement Calculator
Find out when you can retire based on your date of birth and target retirement age.
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Countdown Calculator
Count down the exact days, hours, and weeks until any future event or deadline.
Add or Subtract Time
Add or subtract hours, minutes, and seconds from a time value. Useful for scheduling and time tracking.
Weeks Between Dates
Calculate the exact number of weeks (and remaining days) between any two dates.
Months Between Dates
Calculate the exact number of months and days between two dates.
Results are estimates for informational purposes only and do not constitute professional financial, medical, legal, or technical advice. Read full disclaimer →