Duration Between
Enter time in HH:MM format (24-hour)
Enter Your Values
Select dates and times or enter a value to convert, and your time duration results will appear here.
How to Use the Time Duration Calculator
Choose Your Mode
Select one of three modes: 'Duration Between' to find the gap between two dates/times, 'Add / Subtract' to find a resulting date after adding or removing a duration, or 'Convert Units' to translate a time value from one unit to another.
Enter Your Dates or Values
In Duration Between mode, click the date pickers to select start and end dates, then optionally type start and end times in HH:MM format. In Add/Subtract mode, select a starting date, choose Add or Subtract, then fill in years, months, days, hours, and/or minutes. In Convert mode, type a numeric value and choose source and target units.
Read Your Results
Results appear automatically. Duration Between shows a breakdown bar chart plus total days/hours/minutes/seconds and a working days comparison. Add/Subtract shows the resulting date and day of week. Convert shows the converted value plus a bar chart of all equivalent unit values.
Export or Print
Click 'Export CSV' to download your results as a spreadsheet-compatible file. Click 'Print' to open the browser print dialog for a physical or PDF copy.
Frequently Asked Questions
How is the working days count calculated?
Working days are calculated by iterating through each calendar day from the start date to the end date and counting only Monday through Friday. Saturdays and Sundays are excluded. Public holidays are not factored in because they vary by country and region. If you need to account for specific holidays, subtract the number of holiday days from the displayed working days count.
What does the Add/Subtract mode do with month-end dates?
When adding months and the resulting month is shorter than the starting date's day, the calculator snaps to the last valid day of the target month. For example, adding one month to January 31st yields February 28th (or 29th in a leap year). This follows standard calendar arithmetic used in scheduling systems.
Why are months and years approximate in Convert mode?
In Convert mode, months are defined as exactly 30 days and years as exactly 365 days. These are mathematical approximations for bidirectional conversion. The Duration Between mode uses real calendar arithmetic with actual month lengths and leap years for precise results.
Can I calculate how many days until a future event?
Yes. In Duration Between mode, set the start date to today and the end date to your event. The calculator shows total days remaining plus a breakdown in years, months, weeks, days, hours, and working days. The tool handles dates far into the future.
How do I find a date 90 days from today?
Use the Add/Subtract mode. Select today as the starting date, choose Add, enter 90 in the Days field, and leave other fields at zero. The result date appears instantly with the day of week shown. If it falls on a weekend, the tool flags it.
How do I convert hours to days or weeks?
Use the Convert mode. Enter your number of hours, select hours as the From Unit, and choose days or weeks as the To Unit. The bar chart below also shows equivalent values in all other units simultaneously.