Age Calculator
Guide: BMI Explained: What It Means and What It Does Not
Nothing you enter or choose here leaves your device. This tool runs in your browser.
How to use
- 1Enter the date of birth.
- 2Leave the second date as today, or pick another date to find the age on that day.
- 3Read the exact age and the totals in months, weeks, days and hours.
- 4See the weekday of the birth and how many days are left until the next birthday.
Frequently asked questions
How is the exact age worked out?
It counts complete years, then complete months, then the remaining days since the date of birth, the same way people count age in everyday life.
What about people born on 29 February?
In years that aren't leap years, the birthday is counted on 28 February, so the calculator always shows a next birthday.
Can I find the age on a past or future date?
Yes. Change the "Age on this date" field, for example to see how old someone was at an event or how old they will be next year.
Is my date of birth stored?
No. It stays in your browser and isn't sent anywhere.
Read the guides
Learn how this works and how to get the most from it.
Money, health & time
BMI Explained: What It Means and What It Does Not
How body mass index is calculated, what the standard categories are, and why BMI is only a rough screening tool and not a diagnosis.
1 min read
Money, health & time
How Pregnancy Due Dates Are Calculated
How a due date is worked out from the last period or conception, how cycle length changes it, and what the weeks and trimesters mean.
1 min read
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