Years & Months
Understand longer date ranges using calendar units.
InfoJano › Date Calculator › Date Duration
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MAR15
FREE ONLINE TOOL
Date Duration Calculator
See the full duration between two dates at a glance.
YearsMonthsWeeksDays
Free Date Duration
Understand how much time passes between two calendar dates. Get a calendar-aware breakdown in years, months and days instead of relying only on a rough day total.
Weeks & Days
See the total in weeks and remaining days.
Calendar Aware
Account for different month lengths and leap years.
Plan Milestones
Useful for memberships, projects and anniversaries.
How to Use This Calculator
Choose Start Date
Enter the date your duration begins.
Choose End Date
Enter the date your duration finishes.
Calculate Duration
Run the date duration calculation.
Read Breakdown
Review years, months, weeks and days.
What Does Date Duration Mean?
Date duration is the calendar time between a starting date and an ending date. It can be expressed as total days, weeks and days, or complete years, months and remaining days.
How Calendar Duration Works
Month lengths and leap years matter. A calendar-aware duration is not always the same as dividing a total number of days by 30 or 365.
Common Date Duration Searches
How long is it between two dates?
Enter a start date and an end date to see the calendar duration in years, months, weeks and days. This is useful when you need to calculate time between dates, find the length of a project, or check how long ago an event happened.
How many years, months and days are between dates?
A calendar duration is different from a simple day count. Months have different lengths and leap years add an extra day, so a calendar-aware result helps explain the time span more clearly.
Use this free online date duration calculator for age and anniversary planning, project timelines, service periods, subscriptions, employment periods and other date-range questions. For a simple total-day count, use the Days Between Dates Calculator.
Frequently Asked Questions
How do I calculate duration between two dates?
Enter both dates in the calculator and review the calendar-based duration breakdown.
Is date duration the same as total days?
No. Total days is one measure; years, months and remaining days is a calendar-based breakdown.
Does it handle leap years?
Yes. Leap days are considered when they fall within the selected date range.
Can I include the final date?
Use the inclusive end-date option when the final date should be counted.