๐ Business Hours Calculator
Saturdays and Sundays are not counted as business days (holidays are not accounted for).
Enter a start and end datetime and a business hours window (e.g. 9amโ5pm) to calculate the actual number of hours that fall within business hours, excluding weekends and hours outside that window. Handy for estimating project timelines or SLA calculations.
How to use
- Enter the start date and time.
- Enter the end date and time.
- Set the business hours window (start and end hour).
- Hours worked within business hours, excluding weekends, are calculated automatically.
How the calculation works
This tool adds up only the time between a start and end date/time that falls within business hours on weekdays (MondayโFriday). Use it for response times on enquiries, SLA (service level agreement) deadlines or work estimates. For each day it finds where the business hours (such as 9:00โ17:00) overlap the start and end times and adds up the weekday portions. Weekends and time outside business hours are left out. Business hours are whole hours from 0 to 24.
Worked example
Business hours 9:00โ17:00 Thursday, October 1, 2026 15:00 to Monday, October 5 11:00 Thursday 15:00โ17:00: 2 hours Friday 9:00โ17:00: 8 hours Weekend: 0 hours Monday 9:00โ11:00: 2 hours Total 12 hours An enquiry received at 16:00 on Friday with a โreply within 2 business hoursโ target is due at 10:00 on Monday.
Things to be aware of
- Public holidays and company closures are not considered; subtract those days yourself.
- Lunch breaks are included. To exclude them, subtract the break time per day multiplied by the number of days.
- Times use your deviceโs time zone. For business hours abroad, convert to local time first.
FAQ
How are weekends handled?
Saturday and Sunday are not counted as business days, so all hours on those days are excluded from the calculation. Public holidays are not accounted for.
What happens to hours outside the business hours window?
Any hours outside the configured window (e.g. 9amโ5pm), including on the start and end days, are excluded from the calculation.
How is a multi-day range calculated?
It steps through each day from start to end, calculates the overlap between that day's business hours window and the actual start/end times, and sums the overlaps for weekdays only.