Enter a start date and an end date to calculate the exact duration in days, weeks, months, years, weekdays and weekends. Leap years handled.
Your results will appear here.
Enter your values and press Calculate.
Pick a start date and an end date to calculate the exact duration between the two dates. The calculator subtracts the two calendar dates to find the total duration in days, then converts that into weeks, approximate months, and approximate years. It also walks through every day in the range to count how many are weekdays (Monday to Friday) and how many are weekend days (Saturday and Sunday). Months use an average of 30.44 days and years use 365.25 days, which keeps leap years accurate over long ranges. If the end date comes before the start date, you get a friendly message instead of a wrong number.
The core of the calculation is simple: the difference in days equals the end date minus the start date. Both dates are treated as calendar days at noon, which avoids timezone drift. From the day count, weeks equal days divided by 7, approximate months equal days divided by 30.44 (the average month length), and approximate years equal days divided by 365.25 (the average year length including leap years). Weekdays and weekend days are found by stepping through each day in the range and checking its day of the week.
Choose the start date with the first date picker and the end date with the second. The results appear instantly: total days, weeks, approximate months, approximate years, plus the weekday and weekend day split. Use it to measure a project timeline, a notice period, or the time until an event. If you enter an end date that comes before the start date, the calculator shows a message asking you to fix the order instead of showing a negative number.
Take the period from 2026-01-01 to 2026-01-31. Subtracting the dates gives 30 days. That is 30 divided by 7, about 4.3 weeks; 30 divided by 30.44, about 1.0 month; and 30 divided by 365.25, about 0.08 years. Walking through the 30 days: January 1 2026 is a Thursday, so the range holds 22 weekdays and 8 weekend days. The same steps work for any range, from a single week to many years.
Weekdays are Monday through Friday, and weekend days are Saturday and Sunday. The weekday count doubles as a business day count for the common Monday-to-Friday work week. Public holidays are not subtracted, because holiday calendars differ by country and year; if your range includes holidays, subtract them from the weekday total by hand. For payroll, contracts, and sprint planning, this weekday-first view is usually the number that matters.
Set today as the start date and a deadline as the end date to see how many days remain. Project managers use the weekday split to estimate real working time between kickoff and launch. Couples count down to weddings and anniversaries, travelers check trip lengths and visa validity windows such as 30, 90, or 180 days, and HR teams measure probation and notice periods. Because the calculator handles leap years automatically, even multi-year ranges stay accurate.
The calculator counts the calendar days from the start date up to, but not including, the end date. So from 2026-01-01 to 2026-01-31 you get 30 days. This matches how most people measure elapsed time, such as age or days since an event.
Business days are the weekdays in the range: Monday through Friday, excluding Saturday and Sunday. The weekday result on this page is your business day count. Public holidays are not excluded automatically, so subtract any holidays in your country by hand.
Every Saturday and Sunday between the start date and the end date is counted as a weekend day. In the worked example of January 2026, the 30-day range contains 8 weekend days.
Months are approximate: total days divided by 30.44, the average length of a month. Years are approximate too: total days divided by 365.25, which folds in leap years. For exact calendar months between two dates, count full months from the same day number instead.
The day count is exact because it walks the real calendar, so February 29 is included whenever the range crosses a leap year. The 365.25-day year average keeps long ranges accurate, and leap years follow the standard rule: divisible by 4, except centuries, unless divisible by 400.
You get a clear message: End date must be on or after the start date. Swap the two dates and run the calculation again. The calculator never shows a confusing negative duration.
This tool measures the duration between any two dates you choose. A days-from-today calculator adds or subtracts a number of days from the current date to land on a future or past date. They answer different questions, so pick the one that matches what you need.
Yes. Set the start date to today and the end date to the event, such as a wedding, a product launch, or a visa expiry. The day count tells you exactly how much time is left, and the weekday split shows how many working days that includes.