How the days between two dates are counted
This calculator counts the exact number of calendar days between your start and end dates, accounting for varying month lengths and leap years. Whether the count is inclusive or exclusive of the start/end day depends on the use case — this tool shows the raw difference, which you can adjust by ±1 day if you need an inclusive count.
Common uses
Date difference calculations are commonly needed for contract or lease durations, project deadlines, pregnancy due dates, visa or work permit day-counting rules, and tracking countdowns to events.
Weeks and months are approximate
The "months" figure uses an average month length (30.44 days) since calendar months vary from 28 to 31 days — for exact month/day breakdowns between two specific dates, use our Age Calculator, which calculates precise calendar-based year/month/day differences.
Frequently asked questions
Does this include or exclude the start date? The day count reflects the pure difference between the two dates — if you need to count both the start and end day as separate days, add 1 to the result.
Can I calculate a date in the past from today? Yes — enter any two dates in any order; the calculator will show the absolute difference regardless of which is earlier.