How to use Work Day Calculator
To find a deadline, enter your start date and the number of working days to add, then click Calculate. The tool counts forward through the calendar, skipping Saturdays and Sundays, and shows the resulting end date. This is the standard method used in project management for sprint planning, SLA calculations, delivery estimates, and contract deadlines where 'business days' are specified.
To count working days between two dates, switch to Day Count mode, enter the start and end date, and click Calculate. The tool counts every weekday (Monday through Friday) in the range, inclusive of the start date and exclusive of the end date (or inclusive of both — you can toggle this). Use this mode to audit how long a task actually took, calculate billable hours in a period, or verify an SLA compliance window.
Why use our Work Day Calculator?
- Adds business days to a start date while correctly skipping weekends
- Day count mode for counting working days between two dates
- Inclusive/exclusive end-date toggle for precise boundary control
- 100% browser-based — your dates never leave your device
- Fast and precise — handles any date range without limitations
- Calculates forward and backward — add days to a date or count days between two dates
Frequently Asked Questions
Does this tool account for public holidays?
The standard calculation skips Saturdays and Sundays only. It does not account for public holidays by default, because holidays vary by country, region, and even employer. If your project or contract specifies particular holidays as non-working days, you will need to manually add those days to your count or subtract them from the result. Some jurisdictions and contracts define 'business days' to include bank holidays as non-working days — always check the governing definition in your agreement.
When is the start date included in the count?
The start date is typically not counted as a working day — the first working day added is the next business day after the start date. For example, 'deliver within 5 business days starting Monday' means the deadline is the following Monday (Tue=1, Wed=2, Thu=3, Fri=4, Mon=5). However, different industries and contracts have different conventions. The tool includes a toggle for whether to count the start date as day 1 or day 0, so you can match your specific contract language.
What if my start date falls on a weekend?
If you start on a Saturday or Sunday, the tool advances to the next Monday before beginning to count business days. This matches the most common convention: a project that 'starts on a weekend' is practically considered to start on the following Monday. You can override this by checking the 'Allow weekend start dates' option, which keeps the specified date as day 0 and begins counting from there.
How do I calculate an SLA deadline?
An SLA (Service Level Agreement) deadline is typically expressed as a number of business days from an event. To calculate it: enter the event date (e.g., when a support ticket was opened) as the start date, enter the SLA window in business days (e.g., 3 for a 3-day SLA), and click Calculate. The result is the date by which the SLA must be fulfilled. If today is past that date, the SLA has been breached.