Age Calculator
Calculate age from date of birth in years, months, days, total days, next birthday, and useful life statistics.
Enter your birth date above to calculate your age
Calculate your exact age from a birth date in years, months, days, total days, weeks, hours, and minutes.
Age Calculator
Age Calculator
Calculate age from date of birth in years, months, days, total days, next birthday, and useful life statistics.
When to use it
When to use it
Official forms
Check age for forms, school, travel, or eligibility.
Birthdays
Find the next birthday and days remaining.
Life milestones
See total days, weeks, hours, and fun statistics.
How age calculation works
How age calculation works
The tool compares birth date and target date, adjusts for whether the birthday has passed, and calculates exact units.
Age Calculation Systems Around the World
Age Calculation Systems Around the World
| Calculation Method | Birth date to current date (solar calendar) | Lunar calendar, 354-355 days per year | Everyone ages on New Year's Day (traditional system, being phased out) |
| Year Length | 365.25 days (leap year adjustment) | 354.37 days (11 days shorter) | Same as Gregorian but different counting |
| Age at Birth | 0 years old | 0 years old | 1 year old (traditional) |
| When Age Increases | On your birthday | On your Hijri birthday | January 1st for everyone (traditional) |
| Common Usage | Worldwide standard, legal documents | Islamic countries, religious events | South Korea (transitioning to Gregorian) |
| Precision | Years, months, days, hours, seconds | Years and months typically | Years only |
Technical Implementation & Accuracy
Technical Implementation & Accuracy
Our age calculator uses JavaScript's native Date object, supported by all browsers since Internet Explorer 3 (1996). The calculation is accurate to the millisecond level, though displayed in human-readable units. The tool handles all edge cases: leap years (including century rules), daylight saving time transitions, and month-end variations (e.g., born on January 31st, calculating age on February 28th). For international users, the calculator automatically detects your browser's timezone and adjusts calculations accordingly. The live-updating seconds counter uses setInterval() with 1000ms precision, creating an engaging real-time experience. All processing happens client-side using vanilla JavaScript—no server requests, no data storage, complete privacy.