Day Counter

Simply pick a start date and an end date — the calculator instantly shows the exact number of days between the two dates, plus the equivalent in weeks, months, business days, weekend days, and hours.

Enter both dates and the tool returns the precise day count. For example, from January 1 to December 31 of the same year there are 364 days (365 in a leap year). The days between two dates formula is: end date − start date, measured in full 24-hour periods.

Enable the "Include End Date" toggle. This adds 1 to the result so both the start day and end day count toward the total — useful for legal deadlines, billing periods, and event durations where both boundary dates are active days.

To estimate your next period, enter the first day of your last period as the start date, then add your average cycle length (typically 28 days) using the Date Calculator tool. The date to date calculator can also confirm how many days have passed since your last period.

A standard pregnancy lasts approximately 280 days (40 weeks) from the first day of the last menstrual period. Enter that date as the start date and count forward 280 days using the Date Calculator. You can also use this date to date calculator in reverse — enter today and the estimated due date to see how many days remain.

Ovulation typically occurs around 14 days before the next period. Enter the first day of your last period as the start date and count forward by (your cycle length − 14) days. For a 28-day cycle that is Day 14; for a 30-day cycle it is Day 16. The date to date calculator shows the exact calendar date.

Yes. The calculation uses UTC timestamps, so February 29 in any leap year is automatically included when it falls within your date range — no manual correction needed.

Set the start date to the past date you want to measure from and leave the end date as today. The total days figure is the exact number of days that have elapsed since that date.

Calendar days count every day in the range including weekends. Business days count only Monday through Friday, excluding weekends. Both totals appear side by side so you can use whichever fits your purpose — contracts often specify calendar days while project timelines use business days.

Yes — both the start date and end date are fully editable. You can calculate the interval between any two historical or future dates, not just dates involving today.

The calculator shows full weeks plus remaining days automatically. For example, 45 days = 6 weeks and 3 days. Formula: full weeks = ⌊total days ÷ 7⌋; remaining days = total days mod 7.