Age & Date Tools

About Age & Date Tools

Age & Date Tools is an age calculator and date calculator with three modes. Enter a date of birth to get your exact age in years, months, and days, a live count of the total days, hours, minutes, and seconds you have been alive, a countdown to your next birthday and its weekday, your Chinese zodiac and astrological sign, and life milestones such as your 10,000th day. Date Difference counts the days between two dates, with an option to include the start date. Date Calculator adds or subtracts days from any date and shows the resulting day of the week.

How to use

1. Pick a tab: Age Calculator, Date Difference, or Date Calculator.
2. In Age Calculator, choose your Date of Birth to see your age in years, months, and days plus total days, hours, minutes, and seconds.
3. Scroll down for your next-birthday countdown, Chinese Zodiac, Astrological Sign, and Life Milestones.
4. In Date Difference, set From Date and To Date (To Date starts at today); turn on Include start date (+1 day) to count both ends.
5. In Date Calculator, set a Start Date and Amount, then choose Days After or Days Before to get the target date and weekday.

Limitations & notes

• Chinese Zodiac follows the lunar calendar, so a birthday before Lunar New Year gets the previous year's sign; browsers without Chinese calendar support fall back to the calendar year.
• All dates use your device's local time zone, and the live counter measures from midnight on your birth date because no birth time is entered.
• For a February 29 birthday, the next-birthday countdown targets March 1 in non-leap years.
• Day counts compare calendar dates, so daylight saving time changes never add or remove a day.

FAQ

How is my exact age calculated?

The calculator compares your birth date with today and reports the gap in full years, months, and days, borrowing days from the previous month when needed. The live counter shows the total time elapsed since midnight on your birth date.

How do I count the days between two dates?

Switch to Date Difference and pick a From Date and a To Date. You get the total number of days, the span in years, months, and days, the same span in weeks and days, and the total hours and minutes.

What does "Include start date" do?

By default the start day is not counted, so Monday to Tuesday is 1 day. Turning on Include start date adds one day, which is how people often count trips, contracts, or day 1 of a streak.

How do I find the date 90 days from today?

Open Date Calculator, leave the start date as today (or pick another date), enter 90 as the amount, and choose Days After. Choose Days Before to count backward instead; the result shows the date and its day of the week.