Deadline Date Calculator
Finds a due date from a start date and a number of days.
Share sends a link that reopens these numbers. Copy details pastes the full breakdown as a list.
The formula
business days: step over each weekend, 5 weekdays to every 7 days calendar days: start date + days
The count uses the date’s position in the week, so it is exact for any number of days.
What to watch out for
Check how your contract, court or authority defines the count. Some exclude the start date, as here, and some count it, or treat weekends differently.
Frequently Asked Questions
What date is 10 business days from today?
Usually 14 calendar days later, because it crosses two weekends. Ten business days after Monday 3 March 2025 is Monday 17 March 2025.
What if the period starts on a Friday?
The next weekday is day 1, so one business day after Friday 7 March 2025 is Monday 10 March 2025.
How do I count back from a deadline?
Enter the deadline as the start date and choose to count before it. This gives the last date to send, order or file.