Paydays and work days · rules read October 11, 2026
Days between two dates
Enter two dates; the calculator gives the calendar days between them, the count with both ends, and the weeks.
Written by Radif Partners · How the hours are counted · Editorial policy
Days between the dates
364
Thu, Jan 1, 2026 to Thu, Dec 31, 2026
| Calendar days (end minus start) | 364 |
| Counting both dates | 365 |
| Weeks (decimal) | 52.00 |
| Business days, both dates included | 250 |
| Weekend days | 104 |
| Federal holidays on weekdays | 11 |
“Days between” is the difference of the two dates; counting both the first and last day adds one. How this is calculated.
The number of days between two dates is the later date minus the earlier one: from January 1, 2026 to December 31, 2026 that is 364 days. Counting both the first and the last day gives one more, 365, which is the number of days in the year. Both answers are right; they answer different questions. The difference tells you how much time elapses, as on a countdown: from October 12, 2026 to December 25, 2026 there are 74 days. The inclusive count tells you how many dates a period covers, as when you list the days a rental, a trip or an assignment lasted. Month lengths and leap years are handled by the calendar: February 2026 has 28 days, February 2028 has 29, and the whole of 2028 has 366. The calculator shows both figures, the weekend days and the business days, so you can pick the one your situation calls for.
Day 90 or 90 days after?
90 days after the start
January 10, 2027
| Day 90, start counted as day 1 | January 9, 2027 |
| Weekday of that last day | Saturday |
Difference or inclusive count: the fencepost question
A fence ten yards long with a post every yard needs eleven posts. Dates behave the same way. From October 12, 2026 to January 10, 2027 the difference is 90 days, yet the period touches 91 different dates. Neither number is a mistake; the error comes from mixing them up. A countdown, an age in days or the time since an invoice was issued uses the difference. A list of dates, a hotel stay counted in nights plus the checkout day, or a count of days attended uses the inclusive figure.
The calculator reports both, plus the weekend days and business days inside the span. When the question is about work time rather than calendar time, the business days calculator removes weekends and the observed federal holidays listed by the Office of Personnel Management.
| From | To | Difference | Both ends counted |
|---|---|---|---|
| January 1, 2026 | December 31, 2026 | 364 | 365 |
| October 12, 2026 | December 25, 2026 | 74 | 75 |
| February 1, 2026 | March 1, 2026 | 28 | 29 |
| February 1, 2028 | March 1, 2028 | 29 | 30 |
| December 15, 2026 | January 15, 2027 | 31 | 32 |
Months are not a fixed number of days
"One month later" sounds precise but is not a fixed span. From the 15th of December to the 15th of January is 31 days; from the 15th of February to the 15th of March is 28 days in 2026 and 29 in 2028. When a period is written in days, count days; when it is written in months, the calendar date is what matters, and the day count is a by-product. For a span stated in weeks, the weeks between dates page converts days into whole weeks and leftover days.
Leap years follow the Gregorian rule: a year divisible by 4 is a leap year, except century years, which must also be divisible by 400. The next leap day is February 29, 2028. Spans that run across it, such as a 12-month lease running from mid-2027 to mid-2028, hold 366 days rather than 365, which matters when a rent, an interest charge or a daily rate is spread over the days of the period.
Days between dates at work
Workplaces count days constantly: the length of an introductory or probation period, the notice an employee or employer gives, the days left before a benefit enrollment window closes, the days since the last safety incident. The rules for those periods come from the employer's policy, a contract or a specific law, and they differ on whether the first day counts and whether weekends do. The safe habit is to write down both the start date and the end date, not only the number of days, and to check the wording against a calendar. For hours rather than days, the hours calculator handles start and end times, and the date calculator adds a number of calendar or business days to a start date.
Pay periods follow their own count. Federal overtime law, as described in Fact Sheet #23, uses a fixed workweek of 168 hours, seven consecutive days of 24 hours, no matter how many days separate two paydays.