Business Days Calculator
Use it two ways: (1) Count the working days between two dates — weekends are excluded automatically, and you can choose whether to include the start or end date; (2) Add N business days to a start date to find a deadline (e.g. T+3 settlement, contractual notice periods). Everything runs locally in your browser and the URL captures your inputs, so the link can be shared as-is.
Mode
End precedes start — showing the absolute business-day count.
Start date falls on a weekend — it will not count as a business day even when included.
End date falls on a weekend — it will not count as a business day even when included.
Business days
21 business days
Total days
—
Weekend days
—
Resulting deadline
—
Calendar-day offset
—
Weekend days skipped
—
Please enter a valid number
Only Saturdays and Sundays are excluded. Hong Kong public holidays are not yet auto-deducted — adjust manually if needed.
Formula
business days = floor(span / 7) × 5 + count of Mon–Fri in the remainder add N: step day-by-day from the start, skipping every Sat/Sun until you have counted N weekdays
- · Defaults to a half-open interval: start excluded, end included — matches the common phrasing "due N business days from today".
- · Add-N mode follows the T+N convention used in finance: T+0 is the trade date, T+1 is the next business day. Negative N walks backwards through prior business days.
- · Only Saturdays and Sundays are excluded — Hong Kong public holidays (Lunar New Year, Christmas, Buddha's Birthday, etc.) are not yet auto-deducted, so deduct 12–17 days manually if your scenario depends on them.
- · Securities settlement (T+1, T+2, T+3), contractual notice periods, statutory notice under HK's Employment Ordinance, and court response deadlines generally use the "start excluded, end included" convention — that's the default.
- · References: HKEX clearing rules (T+2 cash-equity settlement), HK Labour Department standard employment-contract templates, and the ISO 8601 calendar-date specification.
- · All arithmetic is done with integer Julian-day numbers, so the result is unaffected by time zones or daylight saving and works for any year from 0001 to 9999.
Frequently asked
Does this include Hong Kong public holidays?
Not yet — only Saturdays and Sundays are removed. Hong Kong's 17 statutory holidays and 12 general (bank) holidays overlap and together remove roughly 12–17 additional working days per year depending on which list applies. For payment-in-lieu, lease notices, or court deadlines, cross-check the government holiday gazette for the year and deduct manually.
How do T+1 / T+2 / T+3 settlement dates work?
T means the trade date. T+N means settlement N business days later, with T+0 being the trade date itself and T+1 the next business day. HKEX cash equities settle T+2; US equities moved to T+1 in May 2024; the Hong Kong Stock Connect stays T+1. The "Add N" mode in this tool follows the start-excluded convention, so entering the trade date and N gives you the settlement date directly.
Why does the count default to excluding the start but including the end?
It is the most common phrasing in commercial contracts: "within 10 business days from today" usually means today does not count and the deadline lands on the 10th working day after. The same convention applies to ordinary "how many days apart" speech. If you are counting attendance (e.g. annual leave taken), tick "Include start date" so both endpoints count.
How many business days are there in a year?
Excluding only weekends, you get 260–262 weekdays per year (262 in 2024 because it was a leap year starting on a Monday, 261 in 2025 and again in 2026). After Hong Kong's 17 statutory holidays you are left with 244–246 working days; for the 12 general (bank) holidays the figure is 249–250. Set the date range to Jan 1 – Dec 31 with both ends included and the tool will give you the exact weekend-only number instantly.
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