๐ Date Calculator
Enter a date to calculate
Calculate your current age from a birth date, count the number of days between two dates, or look up the day of the week for any date โ several date calculations in one tool. Useful for figuring out a contract term or planning an event schedule.
How to use
- Choose "Age," "Days Between," or "Day of Week" mode.
- Enter your birth date, or a start and end date, or the date you want to look up.
- The result is calculated and shown in real time.
How the calculation works
This tool does three kinds of date calculation. Age: your age today in years, months and days, plus the number of days since birth. Days between: how many days lie between two dates, also shown as weeks and days. Day of week: which day of the week a date falls on. The months and days of an age count from your last monthly birthday. If you were born on the 31st and a month has no 31st, the last day of that month counts as the monthly birthday (born January 31 โ February 28 or 29). Todayโs date comes from your device.
Worked example
Born January 31, 2000, calculated on March 1, 2026 26 years 1 month 1 day (counting February 28 as the monthly birthday) April 1, 2026 to December 25, 2026 268 days = 38 weeks 2 days December 25, 2026 โ Friday
Things to be aware of
- Days between is the difference between the two dates. If you count the start date as day 1, add 1 to the result.
- Ages increase on the birthday itself, the usual everyday convention. Some legal systems (Japan, for example) treat the age as increasing at the end of the day before.
- If the end date is before the start date, the difference is shown as a negative number.
FAQ
Does it account for leap years correctly?
Yes โ calculations are based on actual calendar dates, so leap years are automatically handled.
Can I check the day of the week for a date years from now?
Yes โ use "look up weekday" mode and enter any date to see which day of the week it falls on.
Is this useful for calculating a contract term?
Yes โ use "Days Between" mode with a start and end date to get the exact number of days in a contract or project period.
Does age show down to months and days?
Yes โ "Age" mode shows not just your age in years but also the additional months and days.
Is this useful for planning an event's schedule?
Yes โ it's handy for checking what day of the week a candidate date falls on, or working backward to figure out how much lead time you have.