Date duration · Days, weeks, months

Time Between Two Dates

Calculate the exact duration between any two calendar dates — days, weeks, months, years, hours, or minutes.

To find the time between two dates, subtract the earlier date from the later one. Jan 1 to Dec 31, 2026 is 364 days (365 counting inclusively). Enter both dates to see the gap in days, weeks, months, and years.

Date Difference

Start date

End date

Include end date in count

Total duration

0days

—

Years0

Months0

Weeks0

Days0

Hours0

Minutes0

Seconds0

How to use this calculator

Pick a start date and an end date. The calculator instantly shows the duration in multiple units. Toggle "Include end date" to count both ends (useful for hotel nights, rental periods, billing cycles).

Common use cases

Project timelines — how many days until a deadline
Pregnancy due dates — weeks elapsed since LMP
Subscription billing — exact days in a billing period
Visa and immigration — counting stay days for compliance
Construction scheduling — total project duration
Anniversary or milestone tracking — days since an event

Why the years/months breakdown matters

"100 days" doesn't tell you intuitively how long that is. The calculator also shows the same duration as years, months, and remaining days using calendar math. So 100 days = 3 months and ~9 days, not "3.33 months."

Questions, answered

Things people actually ask.

Enter the start date and end date. The calculator computes total days, including or excluding the end date depending on your preference. It also breaks the result into years, months, weeks, and days for a human-friendly view.

By default, the calculator counts full days between dates. So January 1 to January 10 = 9 days (the 1st through the 9th, not counting the 10th itself). Toggle 'Include end date' to count it as 10 days instead — useful for billing cycles and rental periods.

Yes by default — every calendar day. To count only weekdays (Mon–Fri), use the Working Days Calculator, which can also exclude US federal holidays.

Yes. If the end date is before the start date, the calculator shows the absolute difference but flags the direction. Useful for things like 'how long ago was this' calculations.

The calculator uses calendar math, not 30-day months. So March 15 to April 15 = exactly 1 month, regardless of whether February or March had 28 or 31 days. This matches how human-readable dates work.

More time tools.

Sources & standards

Where these answers come from

The figures, rules, and standards on this page are based on the official sources below. This information is provided for general reference only and is not legal, financial, or medical advice.