Age Calculator

How age is calculated

This tool calculates your calendar-accurate age by comparing your date of birth to a reference date (today, by default). Unlike a simple day count, it accounts for varying month lengths and leap years to give you a precise breakdown in years, months and days — plus the total number of days you've been alive.

Why calculate exact age?

• Filling out official forms and applications that require exact age
• Planning birthdays, anniversaries or age-restricted eligibility dates
• Curiosity — finding out exactly how many days old you are
• Calculating the age of a document, event, or milestone

Frequently asked questions

Why do some age calculators give a different number of months and days?

Different tools use different methods. Some assume every month is about 30 days long; this calculator uses your actual calendar months (28-31 days) and adjusts for leap years, so the years/months/days breakdown matches your real birthday cycle exactly.

Can I calculate my age on a future or past date instead of today?

Yes. Change the "Calculate age as of" field to any date - a visa application deadline, a retirement date, or a past event - and the tool will show your exact age on that day.

Does this work for calculating the age of anything, not just a person?

Yes. Enter any start date in the "date of birth" field to find the exact age of a document, a company, a marriage, or any other milestone in years, months and days.