The Date Duration Calculator finds the elapsed calendar time between two dates. Enter a start date and an end date to get the absolute difference in total days, complete weeks plus remaining days, hours, and minutes.
Calculation method
Each date is interpreted at midnight UTC. The calculator subtracts the two timestamps, converts the millisecond difference to days, and takes the absolute value, so reversing the dates produces the same duration.
The remaining outputs are derived from total days:
- Complete weeks:
floor(total days / 7) - Remaining days:
total days mod 7 - Total hours:
total days x 24 - Total minutes:
total days x 1,440
Worked example
For 1 January 2026 through 15 January 2026, the difference is 14 days.
- Complete weeks:
14 / 7 = 2 weeks - Remaining days:
14 mod 7 = 0 days - Total hours:
14 x 24 = 336 hours - Total minutes:
14 x 1,440 = 20,160 minutes
What the result means
This is elapsed date-to-date duration, not an inclusive count of named dates. If you want to count both the start and end date as days on a schedule, add one day to the displayed total. For business-day calculations that exclude weekends or holidays, use the Days Between Dates Calculator and confirm its counting convention.
Frequently Asked Questions
Does the calculator include the start date?
No. It measures the difference between the two calendar midnights. An inclusive project or travel count usually adds one day.
Does it account for daylight-saving changes?
The displayed result is based on calendar dates normalized to UTC midnight, so it reports whole calendar days rather than local elapsed clock hours across a daylight-saving transition.
Can I enter the dates in either order?
Yes. The absolute difference means an earlier start date and a later start date return the same number of days.
Limitations
The tool does not calculate business days, public holidays, time-zone offsets, or partial-day times. It also requires valid date strings; invalid dates return an error instead of a result.