Age Calculator
Calculate age from birthdate. Shows days until next birthday, zodiac sign, and day of the week.
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How to Use
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- 1
Enter Birth Date
Enter the birth date of the person whose age you want to calculate.
- 2
Set Target Date (Optional)
To calculate age as of a specific date, change the target date. Defaults to today.
- 3
View Results
Age, days/weeks/months since birth, days until next birthday, Chinese zodiac, and zodiac sign are displayed.
Birth Date
Tap to select from calendar
What is Age Calculator?
Age Calculator is an online tool that accurately calculates age from a birth date. Beyond just years, it shows total days, weeks, and months since birth, days until the next birthday, Chinese zodiac, Western zodiac sign, and day of the week born. You can also set a custom target date to calculate age as of any specific date.
Key Features
- Accurate age calculation in years, months, and days
- Display of total days, weeks, and months since birth
- Countdown to next birthday
- Chinese zodiac and Western zodiac sign display
- Calculate age as of any custom target date
Use Cases
- Checking your exact age in years, months, and days for a form or document
- Counting down the days until your next birthday
- Determining age as of a specific date for school enrollment or eligibility cutoffs
- Confirming age for insurance policies, contracts, or legal requirements
- Finding out what day of the week you were born
- Checking a child's age to determine eligibility for youth sports leagues or programs
FAQ
How is age calculated — does it count the birthday as day 1?
Age increases by 1 the moment your birthday begins (midnight local time on your birth date). So on your birthday, you are already the new age — not the age you were yesterday. This matches how age is counted for legal and official purposes in the US, UK, and most countries.
What about people born on February 29?
In non-leap years, the legal birthday is February 28 (the day before March 1). This tool correctly handles leap-year birthdays and shows the accurate age for every year.
How do I check if someone meets an age cutoff on a specific date?
Change the target date to the cutoff date. For example, to check if a child is 5 before September 1 for kindergarten enrollment, enter their birth date and set the target date to August 31. The result shows their age on that date.
Can I use this for someone else's birthday, not just mine?
Yes. Just enter any birth date — a friend, family member, employee, or historical figure. The calculator is not tied to your own birth date.
Is my birth date data saved or shared?
No. All calculations run entirely in your browser and no data is sent to any server. Your birth date is never stored or shared.