Today
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Defaults to today
Weekends are always excluded. Add public holidays that apply to you.
Frequently asked questions
How does DateCalculatorFree count the days between two dates?
DateCalculatorFree converts both dates to midnight UTC and takes the difference in whole days. Working in UTC — rather than each visitor's local time zone — avoids the off-by-one errors that daylight-saving transitions can cause when subtracting local dates directly. If you're measuring a span that includes both the start and end date (for example, "how many days is a hotel stay"), add 1 to the result shown.
Why do leap years matter for these calculations?
A year is a leap year if it's divisible by 4, except century years, which must also be divisible by 400 — so 2000 was a leap year but 1900 was not. Leap years add a 29th day to February, which shifts every date-difference and age calculation for anyone born in, or measuring a span that crosses, February 29. DateCalculatorFree's calculations use the calendar's actual month lengths, so leap days are accounted for automatically.
How is age calculated in years, months and days?
Age isn't just total days divided by 365.25 — that drifts over a lifetime. DateCalculatorFree calculates age the way a calendar does: it counts whole years between the birth date and the reference date, then whole months from the last birthday, then the remaining days from the last monthly mark. That matches how age is stated on official documents.
What counts as a "business day"?
By default, DateCalculatorFree treats Monday through Friday as business days and Saturday/Sunday as non-working days. Public holidays vary by country and organisation, so they aren't excluded automatically — add any that apply to you in the holidays field and they'll be subtracted from the total, provided they fall on a weekday within your date range.
What date format should I use?
The calculator uses your browser's native date picker, which displays dates in your locale's format but stores them internally as ISO 8601 (YYYY-MM-DD) — the international standard that sorts correctly and avoids the day/month ambiguity of formats like 03/09/2026.
Does DateCalculatorFree store or send my dates anywhere?
No. Every calculation runs in your browser using JavaScript's built-in date arithmetic — nothing you type is sent to a server or saved once you close the tab. See our Privacy Policy for details on cookies used for advertising.