How to use it: Choose a start date, enter the duration of your task in days, weeks, or months, and decide whether to include or exclude weekends. The calculator will then show you the exact date your deadline falls on.
Calculated Deadline
Monday, December 15, 2025
This is the projected end date for your task or project.
How It's Calculated
The deadline is calculated by adding the specified duration to the start date. The core logic changes based on whether weekends are included or excluded.
- Including Weekends: This is a simple calendar addition. The calculator adds the exact number of days, weeks, or months to the start date. For example, adding 10 days to a Friday includes two weekends in the count.
- Excluding Weekends: This method only counts business days (Monday to Friday).
- If the unit is 'days', it adds that many business days, skipping Saturdays and Sundays.
- If the unit is 'weeks' or 'months', it first converts them to an approximate number of business days (1 week = 5 business days; 1 month ≈ 22 business days) and then performs the calculation.
Example Calculation
Let's review the calculation based on your inputs:
- Start Date: December 1, 2025
- Duration: 10 days
- Exclude Weekends: Yes
Because weekends were excluded, the duration of 10 days was converted into 10 business days.
- We counted forward 10 weekdays from December 1, 2025.
- This covered a span of 10 business days spread across 14 calendar days.
- The final deadline fell on December 15, 2025.
Software Sprint Planning
A team begins a 10-day sprint on a Monday and counts every day, including weekends, to determine the release date.
- Start: Monday, April 1, 2024
- Duration: 10 days
- Exclude Weekends: No
Deadline
Apr 11, 2024
How this example was calculated:
- Start counting from April 1, 2024.
- Add the duration directly on the calendar: Add 10 calendar days.
- The resulting date is April 11, 2024, which is 10 calendar days after the start (8 business days across that span).
Client Proposal Timeline
You have three working weeks to prepare a proposal starting on a Wednesday and want to skip weekends.
- Start: Wednesday, May 8, 2024
- Duration: 3 weeks
- Exclude Weekends: Yes
Deadline
May 29, 2024
How this example was calculated:
- Start counting from May 8, 2024.
- Convert the duration to business days: 3 weeks × 5 = 15 weekdays.
- The resulting date is May 29, 2024, which is 21 calendar days after the start (15 business days across that span).
Marketing Campaign Launch
A marketing campaign begins on the first day of the month and must launch two months later while only counting business days (approx. 22 days per month).
- Start: Saturday, June 1, 2024
- Duration: 2 months
- Exclude Weekends: Yes
Deadline
Aug 1, 2024
How this example was calculated:
- Start counting from June 1, 2024.
- Convert the duration to business days: 2 months × 22 ≈ 44 weekdays.
- The resulting date is August 1, 2024, which is 61 calendar days after the start (43 business days across that span).