Result
Next Birthday
Find your exact age in years, months, days, hours — or calculate any date gap instantly.
Everything above is free and unlimited. Pro adds tools for people who juggle a lot of dates:
Want to try first? Use demo code AV-AGE-CALCULATOR-DEMO to preview every Pro feature on this device.
Most people know their age in whole years, but there are dozens of situations where you need precision down to months, weeks, or even days. Medical eligibility cutoffs, visa applications, insurance underwriting, retirement planning, and legal proceedings all depend on an exact age on a specific date — not just the year you were born.
Our age calculator does more than subtract years. It accounts for the variable length of months, leap years, and calendar edge cases like February 29 birthdays. You get your age broken down into years, months, and days, plus the complete running totals: exactly how many weeks you have been alive, how many days, and how many hours. For newborns and toddlers, weeks and days are often the most meaningful unit — pediatricians track development this way, and so can you.
Beyond personal age, the date-difference mode handles any two calendar dates. Project managers use it to count days between a kickoff and a deadline. HR teams confirm probationary periods. Landlords calculate lease lengths. Students count days until exams. Toggle the business-days filter and weekends are excluded automatically — giving you the true working-day count without manual counting on a calendar.
The date difference tool works in both directions and handles multi-year spans correctly. Whether you need the number of calendar days between two contract dates or the exact number of working days remaining in a project, this tool delivers the precise count immediately.
Need to know what date falls 90 days from today? Or what date was 6 months before a contract started? The add/subtract mode accepts years, months, and days independently. It handles month-end boundaries correctly — when you add one month to January 31 and February has no 31st, the result rolls forward to March 3rd, and the result card notes this adjustment. You also see the day of the week for the resulting date.
This mode is particularly useful for legal and business deadlines where contract clauses specify durations in months or years rather than calendar days. Enter the start date, set the duration, and the result is instant.
Enter a date of birth and the calculator automatically shows how many days, hours, and minutes remain until the next birthday — and which age will be celebrated. The countdown updates based on the current system time. For birthdays falling on February 29 in non-leap years, the calculator uses February 28 as the anchor date, matching the most common legal interpretation. The zodiac sign for the entered date of birth is also displayed — useful for astrology fans, greeting card selections, and personality quizzes.
All calculations run entirely in your browser using JavaScript. No personal data — including your date of birth — is sent to any server. The calculator uses standard calendar arithmetic with correct leap year handling (divisible by 4, except centuries unless also divisible by 400). Results may differ slightly from legal age determinations in jurisdictions with specific birthday rules; always confirm important age thresholds with a qualified professional.
Once you enter a date of birth, the calculator opens up a live "life in numbers" panel that keeps ticking in real time. You can see exactly how many seconds, minutes, hours, days and weeks you have been alive, how many times you have travelled around the Sun, and a few playful estimates such as roughly how many times your heart has beaten and how many full moons have passed since you were born. These running totals update every second, which makes them a fun, shareable way to mark how far you have come — and a surprisingly useful sanity check for newborns and toddlers, whose age is most meaningful in days and weeks.
Every date of birth carries a small bundle of traditions, and the calculator surfaces them automatically. You will see your Western star sign, the traditional birthstone and birth flower for your birth month, your animal in the twelve-year Chinese zodiac cycle, the day of the week you were born, and the generation you belong to — from the Silent Generation and Baby Boomers through Generation X, Millennials, Generation Z, Generation Alpha and the newest Generation Beta. These details are perfect for birthday cards, gift ideas, trivia and personality quizzes, and they are calculated instantly from the date you enter without any lookup tables to scroll through.
If you are the person who always remembers everyone's birthday — or wants to — the Pro birthday tracker keeps a private, on-device list of family, friends or teammates and automatically sorts them by whose birthday comes next, showing each person's current age along the way. From there you can export a recurring calendar file (.ics) that drops every birthday into Google Calendar, Apple Calendar or Outlook so the reminders repeat each year, download the whole list as a CSV, or run a batch calculation that turns a pasted list of dates into a full age table in one click. Teachers checking enrolment cut-offs, sports clubs confirming age groups and HR teams verifying eligibility all use this kind of bulk age calculation, and here it stays completely private to your browser.
Browse the AppVitamins store → — own Age Calculator Pro as a one-time purchase, or get the All-Access pass for every app.
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