Work out the time between two dates, add or subtract years, months and days, calculate an exact age, find which weekday a date falls on, or count business days between two dates.
📊 Calculate Date Difference
📝 Detailed Breakdown
➕ Add or Subtract Days
🎂 Age Calculator
🎉 Fun Facts
📆 Find Day of Week
ℹ️ Additional Information
💼 Business Days Calculator
📊 Breakdown
💡 Note
This calculator excludes weekends (Saturday and Sunday) but does not account for public holidays. For accurate payroll calculations, please manually subtract public holidays from the result.
What this date calculator does
- Date Difference: total days between two dates, plus the same span as years, months and days, weeks, hours, minutes and seconds.
- Add/Subtract: adds or subtracts years, months and days from a date, and shows the weekday, week number and day count.
- Age Calculator: exact age in years, months and days on any date, with days to the next birthday.
- Weekday Finder: the weekday, day of the year, quarter and whether the year is a leap year.
- Business Days: counts Monday to Friday days between two dates, including both the start and end dates.
How it works
The “years, months and days” breakdown is based on the calendar, so it follows real month lengths. The decimal years and months shown beside it are approximations that use a 365-day year and a 30-day month. Whole-day counts are taken between calendar dates, so daylight-saving changes do not add or remove a day.
When you add months, a day that does not exist in the target month moves to the last day of that month. For example, 31 January 2026 plus one month is 28 February 2026.
Worked example: from 1 January 2020 to 30 October 2026 is 2,494 days, or 6 years, 9 months and 29 days. From Monday 26 October 2026 to Sunday 1 November 2026 there are 7 calendar days and 5 business days.
A year is a leap year if it is divisible by 4, except years divisible by 100 unless they are also divisible by 400. The week number shown is a simple count (day of the year divided by 7, rounded up), not the ISO week number.
Things to keep in mind
The business-day count skips Saturdays and Sundays only. It does not know about public holidays, which differ by country and region. The dates you enter stay in your browser and are not sent to this website.
Frequently asked questions
Does it include the start and end date?
The Date Difference tab counts the days between the two dates. The Business Days tab includes both the start and the end date.
What if my end date is before my start date?
Date Difference shows the same span either way. Business Days asks you to enter an end date on or after the start date.
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