Date Difference Calculator — Days Between Any Two Dates
Planning a deadline, a visa appointment, a project sprint or a baby milestone? Pick two dates and get the gap in days, weeks, months, years, hours — plus a Mon–Fri working-day count for project planning. Dates can be entered in either order; the tool always returns a positive span.
🔒 100% Private — runs in your browser, nothing is uploadedHow to Use This Date Difference Calculator (Step-by-Step)
- Choose start and end dates — Any order — the tool normalizes them.
- Click Calculate — All units appear at once.
- Use working days for planning — Weekends are excluded automatically for business estimates.
Counting Days Across Calendars — Under the Hood
The calculation converts both dates to UTC midnight timestamps and divides the millisecond gap by 86,400,000 — rounding absorbs daylight-saving edges. Working days are counted by walking each date and rejecting Saturday and Sunday, which is why a 3-month project estimate stays accurate even when month lengths differ.
Frequently Asked Questions
Are both dates counted?
The difference excludes the start day; add 1 for inclusive counts.
Are public holidays excluded?
Weekends are; holidays vary by country so they are not included.
Does it handle leap years?
Yes — day counts are exact across any century span.