Age Calculator
Find your exact age in years, months, and days.
About the Age Calculator
Your age is more than a single number. From one date of birth, this calculator works out exactly how many years, months, and days you have lived, along with your total days and weeks — and a countdown to your next birthday.
Pick your date of birth and, if you like, an “age at date” to measure against; it defaults to today. The breakdown counts complete months first and derives the leftover days from the real elapsed time, so end-of-month birthdays and leap years come out right. Everything is calculated in your browser, so nothing is uploaded or stored.
How to use it
- 1Enter date of birth. Pick your birth date in the “Date of birth” field.
- 2Set the reference date (optional). Leave “Age at date” on today, or choose any past or future date.
- 3Read the results. Your exact age plus total days, weeks, and next-birthday countdown appear instantly.
Frequently asked questions
How is exact age calculated?+
The calculator counts full years and whole months from your birth date to the reference date, then adds the leftover days measured from the last completed month. This avoids negative day counts around short months and end-of-month dates.
Can I calculate age on a future or past date?+
Yes. Set the optional “Age at date” field to any date to see how old someone is — or will be — on that day. Leave it as today (the default) for your current age.
Does it handle leap years?+
Yes. Month and day counts use real calendar lengths, so February 29 and leap years are handled correctly.
What are the total days and weeks figures?+
Below the years/months/days, the tool shows your whole lifespan as a total number of days and the equivalent whole weeks — handy for milestone counts.
What if I enter a birth date after the reference date?+
No result is shown. The birth date must be on or before the “age at date” for the calculation to run.
Is my birth date kept private?+
Yes. The dates never leave your browser — there is no upload and no sign-up.
Related tools
Date Duration Calculator
Count the days, weeks, and months between two dates.
Dog Age Calculator
Convert your dog's age to human years by breed size.
Time Tracker
Track work, study, and break time, see today’s summary, and pin draggable, resizable sticky notes.
BMI Calculator
Calculate your Body Mass Index from height and weight.
Calorie Calculator
Estimate your daily calorie needs (TDEE) and deficit target.
Percentage Calculator
Work out percentages, ratios, and percent changes.
More free tools
QR Code Generator
Create a QR code from a link, Wi-Fi, contact, email, or SMS.
Image Resizer
Resize any image by pixels or percentage, in your browser.
Merge PDF
Combine multiple PDF files into one, in order.
Unit Converter
Convert length, weight, temperature, and more.
JSON Formatter
Format, validate, explore, and minify JSON.
Password Generator
Create strong, random passwords instantly.