Age Calculator
Free age calculator to find your exact age in years, months, and days. Also shows total weeks, hours, zodiac sign, and days until your next birthday.
Embed this calculator
Copy and paste this code into your website. The embed includes a "Powered by CalculatorSwitch.com" footer with a backlink.
Dimensions: 100% width, 650px height, fully responsive.
Attribution: Includes "Powered by CalculatorSwitch.com" footer with backlink (required for free use).
Styling: Clean minimal design with rounded border, optimized for embedding.
Purpose
The age calculator is a simple yet powerful tool that determines your exact age based on your date of birth. Whether you need to know your precise age for legal documents, medical forms, or just curiosity, this calculator provides accurate results down to the day. It goes beyond simple year calculation by accounting for months and days, giving you a complete picture of your age. The calculator also provides fun extras like your zodiac sign, the day of the week you were born, and a countdown to your next birthday.
How to use
Using the age calculator is straightforward:
- Enter Your Birth Date: Select or type your date of birth using the date picker
- Optional - Calculate As Of Date: By default, your age is calculated as of today. You can change this to calculate your age on any specific date (past or future)
- View Results: The calculator instantly shows your age in years, months, and days, along with additional information
The results include:
- Exact age (years, months, days)
- Total age in months, weeks, days, hours, and minutes
- Days until your next birthday
- Your zodiac sign
- The day of the week you were born
Examples
Example 1: Simple Age Calculation
Birth Date: July 4, 2000
Today's Date: January 11, 2026
Result:
- Age: 25 years, 6 months, 7 days
- Total Days: 9,322
- Zodiac Sign: Cancer
- Born on: Tuesday
Example 2: Calculating Age for a Specific Date
Birth Date: December 25, 1995
Calculate As Of: December 25, 2025 (30th birthday)
Result:
- Age: 30 years, 0 months, 0 days
- Days Until Birthday: 0 (it's your birthday!)
Example 3: Child's Age in Months
Birth Date: September 15, 2024
Today's Date: January 11, 2026
Result:
- Age: 1 year, 3 months, 27 days
- Total Months: 15
- This is useful for pediatric milestone tracking
FAQ
How does the age calculator handle leap years?
The calculator accounts for leap years automatically. When calculating total days or determining if February 29 falls within the date range, it correctly handles the extra day in leap years. For age calculations, if you were born on February 29, your birthday in non-leap years would technically be either February 28 or March 1, depending on interpretation.
Why might my calculated age differ by a day from what I expected?
Age calculations can differ based on whether you count the birth date as day 0 or day 1. Our calculator follows the common convention where you complete a year of age on your birthday. Additionally, timezone differences between when you enter the date and your actual local time can cause a one-day difference.
Can I calculate someone's age at a future date?
Yes! Simply enter the birth date and set the "Calculate Age As Of" field to any future date. This is useful for planning events, determining eligibility for age-restricted activities, or calculating when someone will reach a milestone age.
How accurate is the zodiac sign calculation?
The zodiac signs are based on the Western (tropical) zodiac system, which divides the year into 12 equal parts. The date ranges used are the most commonly accepted ones. However, some sources may vary by a day or two at the boundaries between signs.
What's the difference between chronological age and biological age?
Chronological age is your actual age based on your birth date (what this calculator shows). Biological age refers to how old your body seems based on health markers, lifestyle, and genetics. Someone might be chronologically 50 but have the biological markers of a 40-year-old or a 60-year-old.
How do I calculate age in months for a baby?
Enter the baby's birth date and check the "Total Months" value in the results. This is commonly used for tracking infant developmental milestones. For example, a baby born 18 months ago would show 18 in the Total Months field.
Methodology
The age calculator uses precise date arithmetic to determine your exact age:
Basic Age Calculation:
- Calculate the difference in years between the birth date and target date
- Adjust for months: If the current month is before the birth month, subtract one year
- Adjust for days: If the current day is before the birth day (within the same month), subtract one month and add the remaining days from the previous month
Example Calculation:
If born on March 15, 1990, and today is January 11, 2026:
- Years: 2026 - 1990 = 36, but since January < March, it's 35 years
- Months: January is 10 months after March (counting forward), so 9 months
- Days: Calculate remaining days
Total Time Calculations:
- Total Days = (Target Date - Birth Date) in milliseconds / (1000 * 60 * 60 * 24)
- Total Weeks = Total Days / 7
- Total Hours = Total Days * 24
- Total Minutes = Total Hours * 60
Validation & Accuracy
Tested: Verified against multiple calendar calculation tools and date libraries.
Accuracy: Handles leap years correctly. Results match standard date arithmetic used in programming languages and spreadsheet applications.
Limitations:
- Does not account for timezone differences
- Assumes Gregorian calendar throughout
- Birth times are not considered (calculates based on dates only)