Hours and calendar days
See exact elapsed hours alongside calendar-date counts, which makes daylight-saving changes and partial days transparent.
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Calculator · Dates, time & workdays
Date & Time Calculator
Count the exact time between two moments, understand the calendar and working-day breakdown, or move any date forward and backward.
Dates stay in your browser
Timeline
Choose two moments
Time zone: Local browser time
Your timeline, precisely.
Enter valid dates and times to see exact elapsed time, calendar days, and working-day totals.
How it works
Flexible date math without hidden assumptions.
Choose exactly what a counted day means, while keeping real elapsed time and calendar dates visible beside it.
- 01
Choose a calculation
Find the difference between two date-times, or add and subtract time from one starting point.
- 02
Set counting rules
Include or exclude either endpoint, count calendar days or workdays, and add optional holiday exclusions.
- 03
Review the timeline
See exact elapsed time, calendar weeks, weekdays, weekends, business days, and the resulting date.
Precise where it matters
Elapsed time, calendars, and work schedules together.
Business-day rules
Exclude Saturdays, Sundays, and your own holiday dates when counting workdays or adding business days.
Real calendar arithmetic
Add months and years with end-of-month clamping, and add calendar days without pretending every month has the same length.
Date calculator questions
Endpoints, weekends, hours, and calendar arithmetic.
How do I calculate the number of days between two dates?+
Enter a starting and ending date. The calculator shows both the calendar dates apart and a configurable day count that can include or exclude the start and end dates.
Can I include both the start date and end date?+
Yes. Turn on Include start and Include end. Endpoint settings apply to calendar-day, weekday, weekend, and business-day counts; exact elapsed hours do not change.
How are business days calculated?+
Business days are Monday through Friday, excluding any valid holiday dates you enter. Saturdays and Sundays are treated as weekends.
Can I exclude weekends when adding days?+
Yes. In Add or subtract mode, choose Business days. The calculator skips Saturdays, Sundays, and optional holidays.
Why can the elapsed hours differ from calendar days multiplied by 24?+
Date-time subtraction measures real elapsed time. Around daylight-saving transitions, a local calendar day can contain 23 or 25 hours.
What happens when adding one month to January 31?+
Month and year arithmetic clamps to the final valid day of the destination month, so January 31 plus one month becomes the last day of February.
Are my dates stored?+
No. All date and time calculations happen locally in your browser and are not uploaded or saved.
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