AgeClocks.com – Your Age, Your Way
Our age calculator works out your age in years, months, and days from a date of birth. You can also measure the time span between any two dates.
For convenience, results appear in multiple time units: years–months–days (or months–days only), plus total weeks, total days, total hours, total minutes, and total seconds.
Privacy first: All calculations happen in your browser — nothing is uploaded.
Free Date of Birth to Age Calculator – How Old Am I Today in Years, Months & Days?
Classic Age Calculator
Reverse Age Calculator – What’s My Birth Date If I’m X Years Old?
Reverse Age Finder
Event Age Calculator – How Old Will I Be On a Specific Date?
Age at a Future/ Past Event
Age in Units Calculator – How Old Am I in Days, Weeks, Months, Hours & Seconds?
Age in Units
Planet Age Calculator – What’s My Age on Mars, Jupiter, Venus & Other Planets?
Age on Other Planets
Shared Age Finder – Compare Ages & Find Age Gaps
Compare / Shared Age Finder
Life Clock – How Much of My Life Have I Lived?
Life Clock
Zodiac Sign Finder – What’s My Star Sign, Chinese Zodiac & Birthstone?
Zodiac & Birth Details
Find Date of Birth from an Age
Know an age but not the exact birthday? Switch the setting to Age, save, and enter age in years (or years and months). The calculator will show the possible birth date range for the selected “as-of” date.
What Is My Age?
Enter your date of birth and today’s date to see your current age. You can also choose a different end date to find your age on a future or past day. At the bottom of the results, you’ll see days remaining until your next birthday (or event date).
How Old Is My Child?
For newborns and infants, it’s common to track age in weeks or months. AgeClocks.com shows both automatically for any date range.
Enter your child’s date of birth and click Calculate. The “Find Age On” fields default to today, but you can choose any future date. The calculator displays weeks old and, when relevant, months old.
How Age Is Calculated
We use two complementary methods:
- Calendar-style age: returns years–months–days (and months–days). For consistency, years are treated as 365 days and months as an average of 30.4167 days (365 ÷ 12). This mirrors everyday language—e.g., “15 years old”—without separating regular and leap years.
- Exact total days: computes the precise number of days between two dates using programming date functions that account for real leap years and month lengths. From there, we also convert that span into weeks, hours, minutes, and seconds.
Exact Days Formula (Concept)
Total days = (365 × number of non-leap years) + (366 × number of leap years) + days in the partial year(s).
Example: born on March 5 and checking on June 7—AgeClocks.com counts the precise days between these dates and also expresses the result as years, months, and days.
How Many Days Until…?
Calculating days to a future date by hand requires handling leap years and different month lengths. Here’s a quick reference:
Days in Each Month
- January – 31
- February – 28 (29 in a leap year)
- March – 31
- April – 30
- May – 31
- June – 30
- July – 31
- August – 31
- September – 30
- October – 31
- November – 30
- December – 31
To quickly find days until a birthday, holiday, or trip (within the next year), add the days for each full month in between, then include the remaining days in the starting and ending partial months.
Tip: Use AgeClocks.com to do this instantly—enter today as the “Date of Birth” and your target date as “Find Age On.” The output will show the exact number of days to go.
Date Inputs & Counting Method
- Single-digit days are fine (no leading zero required).
- Always use a 4-digit year.
- Counting starts after the start date (day 0). For example, 03/15/2022 to 03/18/2022 equals 3 days: the 16th is day 1, the 17th day 2, and the 18th day 3.
Calculate Age from Birthdate in Excel
Store the birthdate in cell A1 as MM/DD/YYYY, then use:
- Years:
=DATEDIF(A1, TODAY(), "Y") - Months (remaining):
=DATEDIF(A1, TODAY(), "YM") - Days (remaining):
=DATEDIF(A1, TODAY(), "MD")
Combine them into a single phrase:
=CONCAT(B1, " years, ", C1, " months, ", D1, " days")
(where B1, C1, and D1 hold the three results).
🌏 How Age is Counted in Different Cultures
📅 Common Age Calculation Method
Age calculation varies across cultures. This Age Calculator follows the most common age system, where a person's age increases on their birthday. This method is widely used in Western countries.
🔢 Other Cultural Age Systems
- In some traditions, age is counted based on the current year. A person who is 20 years old could also be described as being in their 21st year of life.
- In the traditional Chinese age system, a newborn is considered 1 year old at birth, and their age increases at the Lunar New Year rather than their actual birthday.
🕰️ Understanding Month and Day Calculations
- Feb. 20 to Mar. 20 is counted as one month.
- Feb. 28 to Mar. 31 can be counted differently based on how end-of-month days are treated.
Frequently Asked Questions
How do I calculate my exact age?
Simply enter your date of birth and the current date above, and AgeClocks will do the rest.
Can I find my age on other planets?
Yes! Try our planet age calculator to see how old you’d be on Mercury, Venus, Mars, and more.
How accurate is AgeClocks.com?
Our tool uses precise date differences, accurate to the second.
Privacy Policy
We respect your privacy. All calculations are done locally in your browser and no data is sent to our servers. We do not use cookies or collect personal information. Third-party ads may collect anonymous usage data as per their privacy policies. We sometimes use affiliate links to keep this site running—thanks for your support! Just a reminder, we’re not responsible for content on external websites.
Terms of Use
By using AgeClocks.com, you agree that the calculations provided are for informational purposes only and should not be used as a substitute for professional advice. We are not liable for any damages resulting from use of this site.