Date, Time & Calendar Tools
Answer questions like how many days until a deadline in a few seconds.
Business Days in a Month
Count business days in any month, excluding weekends and U.S. federal holidays.
Week Number Calculator
Find the ISO 8601 or US week number of any date, look up a week's dates, and see a full year calendar.
Business Day Calculator
Add or count business days and see a monthly calendar with US holidays.
Deadline Start Date Calculator
Work backward from a deadline to find the date to start, with buffer days and milestones.
Quarter Calculator
Find which calendar or fiscal quarter (Q1–Q4) a date falls in, with start and end dates.
Business Days in a Month
Count business days in any month, excluding weekends and U.S. federal holidays.
Week Number Calculator
Find the ISO 8601 or US week number of any date, look up a week's dates, and see a full year calendar.
Business Day Calculator
Add or count business days and see a monthly calendar with US holidays.
Deadline Start Date Calculator
Work backward from a deadline to find the date to start, with buffer days and milestones.
Quarter Calculator
Find which calendar or fiscal quarter (Q1–Q4) a date falls in, with start and end dates.
Category Overview
What Date, Time & Calendar tools can do for you
5 tools listed
The date, time and calendar tools cover everyday date arithmetic. Find the number of days between two dates, add or subtract months and years, check which weekday a date falls on, and count weekdays or business days in a period without counting squares on a calendar.
For planning, you can work backward from a deadline, calculate due dates and renewal dates, convert hours and minutes into decimal hours (8 hours 30 minutes to 8.5), check ISO week numbers and quarters, and count down to an event.
For working across time zones, the world clock and time difference tools help you schedule calls, and the stopwatch, timer and Pomodoro tools help you manage your own time.
Handy when you need to
- ✓ Work backward from a deadline to a start date
- ✓ Count weekdays or business days in a date range
- ✓ Find a good meeting time across time zones
- ✓ Convert hours and minutes to decimal hours for timesheets
Pro tip
Calculations related to pay, such as overtime totals, are in Tax, Salary & Payroll.
Date, Time & Calendar: frequently asked questions
- Q. Do business day calculations include public holidays?
- A. Business day counters skip weekends. Public holidays differ by country, so subtract them yourself if they apply to your period.
- Q. Can I add months to a date?
- A. Yes. The date calculator adds or subtracts days, months and years, and handles month lengths correctly.