Age Calculator
About the Age Calculator
Work out your exact age from your date of birth, broken down into years, months, and days. It is handy for forms, eligibility checks, birthday countdowns, or simply settling how old someone is to the day. The calculation runs entirely in your browser against your device clock — nothing about your birth date is uploaded or stored.
This tool works in your browser: the files and text you use are processed on your device and are not uploaded.
How to use it
- Enter your date of birth.
- Press Calculate Age.
- Read your age as completed years, months, and days.
Frequently asked questions
How is exact age calculated?
The tool counts completed years from your birth date to today, then the leftover months, then the leftover days — borrowing days from the previous calendar month when needed so the result reflects real calendar lengths rather than a flat 30-day month.
Does it account for leap years?
Yes. Because it works directly with calendar dates, February 29ths and varying month lengths are handled automatically, so the day count stays accurate across leap years.
Why does my age in months not simply equal years × 12?
Age is shown as years plus the remaining months and days since your last birthday, not as a total month count. That "3 years, 5 months, 4 days" style is how age is normally expressed for documents and milestones.
Is my date of birth kept private?
Completely. The date never leaves your device — the whole calculation happens locally in your browser with no server call.