Date Difference Calculator
Calculate the number of days, weeks, months and years between any two dates.
How the date difference is calculated
The difference is computed as the absolute number of days between two dates, then broken into weeks, approximate months and approximate years.
Common uses for date difference calculators
Count working days left until a project deadline to plan sprints and task allocation accurately.
Contracts often specify notice periods or payment terms in days. This tool gives you the exact count.
Find out how many days until your next anniversary, or how many days you have been in a relationship or at a job.
Frequently asked questions
What does "include end date" mean?
By default the calculator counts from the start date up to but not including the end date. Enabling "include end date" adds one extra day — useful when you want to count both the first and last day of a range (e.g., a stay from check-in to check-out).
How are working days counted?
Working days are counted as Monday through Friday. Saturdays and Sundays are excluded. Public holidays are not automatically excluded because these vary by region and year.
Can I calculate days between dates in different years?
Yes. The calculator handles multi-year ranges correctly, including leap years, which add an extra day in February every four years.
Why are months and years shown as "approximate"?
Calendar months vary in length (28–31 days), so dividing by 30.44 gives an approximate month count. For an exact breakdown of years, months and days, use the Age Calculator on this site.
What if the end date is before the start date?
The calculator takes the absolute difference, so the result is always a positive number regardless of which date you enter first.