Date Difference Calculator
Pick any two dates and instantly see the gap in calendar days, working days (Mon–Fri), weekend days, plus a year/month/day breakdown and totals in weeks and months. Handy for deadlines, trip planning, visa stay durations and maternity leave.
Please enter a valid number
End date precedes start date — showing absolute difference below.
Days difference
90 days
Years / months / days
—
Working days exclude weekends only — Hong Kong public holidays are not yet deducted.
Working days (Mon–Fri)
—
Weekend days
—
Total weeks
—
Total months
—
Formula
Days difference = |end − start| (using Julian day subtraction) Working days = Mon–Fri count within the (start, end] range Y/M/D breakdown = calendar walk from start to end
- · Calculations use local civil dates only and are unaffected by timezones or DST.
- · Days difference = end − start (a gap). Same day = 0 days; next day = 1 day.
- · “Working days” excludes only Saturdays and Sundays. Hong Kong public holidays (Dragon Boat, Mid-Autumn, etc.) are not auto-deducted — adjust manually if strict bank-business-day counting is required.
- · The Y/M/D breakdown uses a calendar walk (complete months first, then days), matching Excel’s DATEDIF behaviour.
- · Order of inputs does not affect absolute totals. If the end date precedes the start date, an info banner appears and the absolute difference is shown.
- · Supports years 1–9999. Dates use ISO format (YYYY-MM-DD).
Frequently asked
Are “working days” the same as Hong Kong bank business days for contracts or maternity leave?
This tool counts working days as Mon–Fri only — equivalent to Excel’s NETWORKDAYS default (no holiday list). HK bank business days exclude Saturdays, Sundays AND statutory public holidays. Hong Kong’s Employment Ordinance also defines “rest day”, “statutory holiday” and “public holiday” differently. For strict bank-business-day counting, cross-check the Labour Department / HKMA holiday calendar and adjust manually.
From Jan 1 to Jan 2 — is that 1 day or 2 days?
This tool reports the gap (end − start), so Jan 1 → Jan 2 is 1 day. If you need the inclusive count (both endpoints), simply add 1. The classic example is hotels: check in Jan 1, check out Jan 3 → 2 nights, which is exactly what hotels charge for.
What happens if the end date is earlier than the start date?
No error. A small info banner appears and the tool reports the absolute difference (days, working days, etc.). You don’t need to worry about which date goes first — the totals work in either direction.
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