All age calculators
17 free calculators for ages, dates and birthdays — exact, private and quick.
Every calculator on 123AgeCalculator, grouped by what you want to know. For your exact age in years, months and days, start with the age calculator; the others answer more particular questions — a baby's corrected age, a retirement date, a zodiac sign, a pet's age in human years.
Your age
- Age CalculatorExact age in years, months and days, plus totals and your next birthday.
- Age in Days CalculatorDays since you were born, and when you turn 10,000 days old.
- Age in Weeks CalculatorWeeks since birth, plus a "life in weeks" grid.
- Age in Months CalculatorAge in months and days, ideal for babies and toddlers.
- Age in Seconds CalculatorA live counter of your age in seconds, minutes and hours.
- Birthday CalculatorDays until your next birthday and the weekday it lands on.
- Age Difference CalculatorThe exact age gap between two people, and who is older.
- Birth Year CalculatorBirth year — or exact birth date — from an age.
Life stages
- Baby Age CalculatorBaby age in weeks and months, with corrected age for preemies.
- Chronological Age CalculatorTest-date age in years;months;days, with the working shown.
- Retirement Age CalculatorSocial Security full retirement age and key dates from 62 to 70.
- Generation CalculatorBoomer, Gen X, Millennial, Gen Z or Alpha — by birth year.
Around the world
- Korean Age CalculatorTraditional Korean age, year age and international age.
- Chinese Zodiac CalculatorYour animal and element, placed by Lunar New Year.
Pets & fun
- Planet Age CalculatorYour age in Mercury, Mars, Jupiter and Saturn years.
- Dog Age CalculatorDog years to human years, by size and by DNA.
- Cat Age CalculatorCat years to human years, with the life stage.
Which calculator should I use?
| If you want to know… | Use |
|---|---|
| How old you are, exactly | Age Calculator |
| How many days until your birthday | Birthday Calculator |
| How old a premature baby is, corrected | Baby Age Calculator |
| A child's age for a test score | Chronological Age Calculator |
| When you can claim Social Security | Retirement Age Calculator |
| The gap between two people | Age Difference Calculator |
| What year someone was born | Birth Year Calculator |
| A fun number to share | Age in Seconds or Planet Age |