Work Days Calculator

What this calculator does

This calculator counts business days (work days) between two dates—typically Monday through Friday, excluding weekends. It does not exclude public holidays; for that you would need to subtract holidays manually or use a tool that supports a holiday calendar.

It is useful for project timelines, contract periods, shipping estimates ("5 business days"), and any count of weekdays between two dates. Project managers and office workers use it to plan deadlines. The count is inclusive of both start and end dates when they are weekdays.

How to use it

1. Enter or pick the start date (e.g. project start or order date).
2. Enter or pick the end date (e.g. deadline or delivery date).
3. Read the number of work days in the Result section. This is the count of weekdays (Mon–Fri) in the range, including start and end if they fall on weekdays.

If your context uses a different definition of "business days" (e.g. including Saturday or excluding certain holidays), you will need to adjust the result manually or use another tool.

Formulas used

• The calculator iterates from start to end date and counts each day whose weekday is not Saturday (6) or Sunday (0) in a standard 0–6 weekday representation.
• Inclusive: both start and end count if they are weekdays. So "Jan 1 to Jan 3" with Jan 1 = Monday and Jan 3 = Wednesday counts 3 work days.
• No built-in holiday calendar; holidays are not excluded. For a given country or state, subtract the number of holidays in the range to approximate "business days" as used in contracts or regulations.

Interpretation & examples

• Use for project timelines, contract periods, or "X business days from today" (add X work days to a start date using a calendar).
• Example 1: Jan 1, 2024 (Monday) to Jan 31, 2024 (Wednesday) → 23 work days (excluding weekends only).
• Example 2: Dec 23, 2024 (Monday) to Dec 31, 2024 (Tuesday) → 7 work days. Holidays (e.g. Christmas) are not excluded; subtract them if your context requires it.
• Example 3: A 2-week period that spans 10 weekdays → 10 work days. Useful for "10 business day" delivery or review periods.

History & background

Business-day counting is standard in contracts, shipping, and finance. Different regions define weekends and holidays differently; this tool uses a simple Monday–Friday rule. For legal or contractual "business days," confirm the definition (e.g. excluding federal holidays in the US) and adjust accordingly.

Limitations & safety notes

• Holidays are not excluded. For exact "business days" in a given country or state, subtract the number of holidays in the range or use a calendar that supports holidays.
• Not legal or contractual advice. Confirm how "business days" are defined in your context (e.g. calendar days vs working days, inclusive vs exclusive). When in doubt, get clarification from the other party or a professional.