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Date & Time

Free date & time calculators: age, date difference, a weekly time card with pay, hours between times, business days, a countdown and time duration math.

7 calculators Free and online

📌 About Date & Time

Counting time by hand is error-prone — overnight shifts, leap years, weekends and different month lengths all trip people up. These calculators handle the calendar and the clock correctly, whether you are adding up a work week, counting down to a date, or measuring the exact gap between two days.

Each tool counts in real units and accounts for things like overnight hours, leap years and weekends automatically. Use them to fill out a timesheet, find your exact age, count business days for shipping or Net-30 terms, or run a countdown to an event.

  • Fill out a weekly time card and get total hours plus gross pay with overtime
  • Find the hours between two clock times, including overnight shifts
  • Add or subtract time durations in hours, minutes and seconds
  • Calculate your exact age, or the difference between any two dates
  • Count business days between dates or add business days, skipping holidays
  • Run a countdown of the days until a future date

🧮 Calculators in this category

Date Math

Business Days Calculator — Working Days Between Two Dates
Count the working days (Monday–Friday) between two dates, skip weekends and holidays, or add a number of business days to a start date.
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Days Until Calculator — Countdown to Any Date
Count how many days from today until any future date — with weeks, months and a live days-and-hours readout, and past dates shown as 'days ago.'
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Date Difference Calculator — Days, Weeks & Business Days Between Two Dates
Count the exact time between any two dates: total days, weeks, months, years and business days (weekends excluded).
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Time & Hours

Hours Calculator — Hours Between Two Times (with Breaks)
Find the hours between a start time and an end time — overnight shifts included — minus any break, shown as decimal hours and h:mm.
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Time Card Calculator — Weekly Timesheet Hours & Pay with Overtime
Add up a full week of clock-in/clock-out times, subtract unpaid breaks, and get total hours, overtime over 40, and gross pay.
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Time Duration Calculator — Add & Subtract Hours, Minutes, Seconds
Add or subtract two time durations in hours, minutes and seconds — with clean carries — and convert the result to total minutes, seconds or decimal hours.
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Age & Dates

Age Calculator — Exact Age in Years, Months, Days & Next Birthday
Find your exact age in years, months and days from a date of birth — plus total days lived, the weekday you were born, and a countdown to your next birthday.
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❓ Frequently asked questions

How do I calculate hours worked on a time card?

For each day, subtract the clock-in from the clock-out and take off any unpaid break, handling overnight shifts; then add the days up. Hours over 40 in a week are usually overtime at 1.5×. The time card calculator does this and adds gross pay.

How do I count the hours between two times?

Subtract the start time from the end time; if the end is earlier (an overnight shift) add 24 hours, then subtract any break. The hours calculator returns both decimal hours and h:mm.

What is the difference between calendar days and business days?

Calendar days count every day; business days count only Monday–Friday and skip weekends (and any holidays you list). Use the date difference calculator for total days and the business days calculator for working days.

How do I count down to a date?

The days until calculator counts the days from today to a future date — useful for a wedding, vacation, due date or deadline — and also shows weeks and months.