Category
Date & Time
Age, date differences, business days, countdowns and duration helpers.
Find exact age in years and days, count business days between dates, convert time zones, and decode Unix timestamps. These tools answer the date-and-time questions that come up in contracts, project planning, developer workflows, and everyday life — without opening a spreadsheet.
7 tools · Private · Browser-only
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Choose the date or time question you need to answer
Use the tools below for calendar dates, elapsed time, or working days. Each result explains the assumptions it uses.
Between two times
Find elapsed hours and minutes, including overnight durations.
Between two dates
Count elapsed days, weeks, and calendar months.
Add or subtract a date
Move a date forward or backward by days, weeks, months, or years.
Weekdays between dates
Count Monday–Friday days while excluding weekends.
Featured calculators
Popular starting points for date & time homework and quick checks.
Age Calculator
Exact age from date of birth.
OpenDate Difference Calculator
Days between two dates.
OpenDate Calculator
Add or subtract days from a date.
OpenTime Duration Calculator
Duration between times.
OpenBusiness Days Calculator
Weekdays between dates.
OpenCountdown Calculator
Time until a target date.
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