Calculate your exact age in years, months, days — and days until your next birthday.
Click the Date of Birth field and enter your birthday using the date picker.
By default today's date is selected. You can change it to calculate your age on any past or future date.
See your exact age in years, months, and days, plus total days lived, total hours, and days until your next birthday.
Very accurate. It accounts for varying month lengths and correctly handles leap years when calculating the exact number of days, months, and years between any two dates.
Yes. Enter any birth date and any target date to calculate age for any person on any past, present, or future date — great for checking ages on specific anniversary dates.
Yes. The calculator correctly handles February 29 birthdays and counts leap year days accurately when computing total days lived and the precise age breakdown.
It shows how many days remain until the person's next birthday, calculated from the target date you selected. Great for birthday planning and countdown countdowns.
Enter your date of birth, leave today as the target date, and click Calculate Age. The Total Days field shows exactly how many days you have been alive as of today.
Simply change the "Calculate Age On" field from today to any date you choose — past, present, or future. The calculator will compute your exact age on that specific date.
The calculator handles leap day birthdays correctly. In non-leap years, your birthday is treated as March 1 for the purpose of computing the next birthday countdown.
Different countries have different age-of-majority laws (18 in most of the world, 19 in Korea and parts of Canada, 20 in Japan and Taiwan, 21 in some US contexts for alcohol). Calculate the exact age in years and days to verify someone meets the threshold for any legal context — contract signing, voting eligibility, insurance underwriting, or compliance reporting.
Many retirement systems calculate eligibility down to the day. Use the calculator to find the precise date you reach a specific age threshold for Social Security (62, 67, 70), 401(k) catch-up contributions (50), HSA catch-up (55), or required minimum distributions (73 under SECURE 2.0). Each "extra day" can mean thousands in benefits.
Most school districts require children to turn 5 (kindergarten) or 6 (first grade) by a specific cut-off date — typically September 1 or August 31. Plug in your child's birth date to confirm eligibility for the current academic year, or to plan when they will be eligible.
Many preventive health screenings are recommended at specific ages: first colonoscopy (45–50), mammogram (40 or 50 depending on guidelines), prostate screening (55), pneumococcal vaccine (65). Knowing your exact age helps schedule timely appointments.
For dogs and cats, the popular "multiply by 7" rule is inaccurate. The first two years of a dog's life equal ~12 human years each; after that, each year is roughly 4 human years. For cats: years 1 and 2 equal 15 and 24 human years; each subsequent year is about 4. Calculate your pet's actual age in days then apply the appropriate conversion for a more accurate estimate.
Accountants and asset managers track exact ages of equipment, vehicles, and software licenses for depreciation schedules and warranty calculations. The calculator works for any "from-date / to-date" pair — substitute purchase date for birth date.
This calculator uses the standard "complete year" method: your age increases by 1 only on the exact day of your birthday each year. Until that day, you remain the previous age — even if your birthday is tomorrow. The remaining "months" and "days" represent the time elapsed since your most recent birthday. For example, if you were born 15 March 1990 and today is 14 March 2026, you are 35 years, 11 months and 30 days old — not 36 yet.
The "total days lived" calculation handles leap years automatically by counting actual calendar days. A person born on 29 February 2000 will have approximately 9,497 days at age 26 (March 2026), accounting for the seven leap years (2000, 2004, 2008, 2012, 2016, 2020, 2024). The "days until next birthday" uses the next actual calendar occurrence — so leap-year babies see their countdown end on 1 March in non-leap years.
Legally and astronomically, you age one year each calendar year. Most jurisdictions treat 1 March as your legal birthday in non-leap years, though some treat 28 February instead. Socially, leap-year babies often celebrate on whichever date they prefer.
Months have different lengths (28–31 days), so "5 months and 10 days" is not the same as "163 days" — the calculator shows you both metrics so there's no ambiguity. Use total days for precise calculations and years/months for normal conversation.
It uses your device's local time zone. For most personal use this is fine. For precise legal or astrological purposes, set your device clock to the relevant time zone first.
Yes — use any date as the "birth date" and any date as "today." The calculation logic works identically whether you are computing someone's age or the gap between two events such as project start/end dates.