Age Calculator
Enter your date of birth to get your exact Western age (years / months / days), Chinese nominal age (虛歲), days lived and days until your next birthday.
Please enter a valid number
Exact age
25 years
Nominal age (虛歲)
26 years
Formula: current year − birth year + 1. You are 1 sui at birth.
Days lived
—
Weeks lived
—
Months lived
—
Days to next birthday
—
Formula
Exact age: complete years, months and days since birth (rolls back if birthday not yet reached) Nominal (虛歲): current year − birth year + 1 Next birthday: days from today to the next (birth month, birth day)
- · Calculation uses local civil dates and is unaffected by timezone or DST.
- · If your birthday has not yet passed, exact age rolls back a year — matching how it appears on your HK ID card.
- · Traditional 虛歲 advances on Lunar New Year. This tool uses the common HK shorthand (current Gregorian year − birth year + 1).
- · For Feb 29 births: the calculator counts Mar 1 as the birthday in non-leap years, and Feb 29 in leap years.
- · Supports years 1–9999. Date of birth cannot be later than the as-of date.
Frequently asked
What is the difference between Western age (實歲) and Chinese nominal age (虛歲) in Hong Kong?
Western age (實歲) starts at 0 on the day you are born and adds one with each birthday — this is what HK ID cards, schools and government forms use. Chinese nominal age (虛歲) counts you as 1 at birth and traditionally adds one every Lunar New Year. The simplified HK formula is current year − birth year + 1, so 虛歲 is typically 1–2 years higher. It still comes up in family settings, fortune-telling and date-picking customs.
I was born on Feb 29 — how is my birthday counted in non-leap years?
The common HK and international convention is to celebrate on Mar 1 in non-leap years and on Feb 29 itself in leap years. The calculator follows this rule so you still age every year (rather than every four).
Can I check what my age will be on a future date (e.g. for an exam or visa)?
Yes. Change the “As of” date to that future date and the tool will compute your exact age on that day. Date of birth must still be earlier than the as-of date or the input is flagged invalid.
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