Age Calculator
Find your exact age in years, months and days – today or on any date you choose. Plus your age in weeks, days and hours, your next birthday and the weekday you were born.
Age calculators for people
- Age Calculator Exact age in years, months and days
- Chronological Age For tests and assessments (SLP, psychology)
- Age Difference Age gap between two people
- Adjusted Age Corrected age for premature babies
- Korean & Lunar Age Traditional East Asian age
Pet age calculators
- Dog Age Calculator Dog years to human years
- Cat Age Calculator Cat years to human years
- Kitten Age Calculator How old is my kitten? By weight and signs
AI photo tools
- How Old Do I Look? AIAI guesses your age from a selfie
- Pet Age From Photo AIAI estimates your dog or cat’s age
- Dog Breed Identifier AIWhat breed is my dog? Upload a photo
- Cat Breed Identifier AIWhat breed is my cat? Upload a photo
- Dog Age From Photo AIUpload your dog’s photo for an age estimate
- Cat Age From Photo AIUpload your cat’s photo for an age estimate
- Exact to the dayCalendar-accurate, including leap years and months of different length.
- Private by designEverything is calculated in your browser. Our AI photo tools never store your pictures.
- People and petsFrom chronological age for testing to dog, cat and kitten age – and AI estimates from a photo.
How to use the age calculator
- Enter your date of birth.
- Leave the second date as today, or pick any date to see how old you were or will be on that day.
- Press Calculate. You get your age in years, months and days, plus totals in months, weeks, days, hours and minutes.
How is age calculated?
Age is counted in whole years since your birth date. The calculator first counts complete years, then complete months, and finally the remaining days. Because months have 28 to 31 days, the result is based on the real calendar rather than an average month length.
Example: someone born on May 15, 1990 is, on September 24, 2026, exactly 36 years, 4 months and 9 days old. From May 15, 2026 (36th birthday) to September 15, 2026 are 4 whole months, and 9 days remain until September 24.
Age on a specific date
Need to know how old someone was on a past date, or will be on a future one – for a school cut-off, a sports age group, a visa form or a retirement plan? Change the second date in the calculator. It works for any date between 1850 and 2999.
How old am I in months, weeks and days?
The result also shows your age as a total number of months, weeks, days, hours and minutes. Parents often use age in months for babies and toddlers, and age in weeks during the first months of life.
What if I was born on February 29?
People born on a leap day celebrate their birthday on February 28 (or March 1) in non-leap years. Our calculator counts February 28 as your birthday in those years, which is also how most legal systems treat it.
Frequently asked questions
How do I calculate my age manually?
Subtract your birth year from the current year. If your birthday has not happened yet this year, subtract one more. For months and days, count forward from your last birthday.
Is my age counted differently in other countries?
Most countries use the international age system shown here. Traditional Korean and Chinese age reckoning counts differently – try our Korean and lunar age calculator.
What is chronological age?
Chronological age is simply the time since birth. Psychologists and speech therapists use it for test scoring, often with special rounding rules – use our chronological age calculator.
Can I find out how old I look?
Yes – our free AI tool How old do I look? estimates your age from a selfie, privately in your browser.