Time & Date Calculators
Calculate date differences, exact age, and time between events. Enter two dates — see days, weeks, months, and years between them. Free.
Time and date calculations are surprisingly complex when accounting for time zones, leap years, business days, and international date formats. These calculators help you find durations between dates, add or subtract time periods, convert between time zones, calculate age precisely, and determine business day counts excluding holidays.
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Time Calculators
Add and subtract hours, minutes, and seconds for any calculation. Enter time values — see the result in HH:MM:SS and decimal hours. Free.
7 calculators
Date Calculators
Calculate age, date differences, and calendar tools. Enter your date — see age, days since/until, and day of the week. Free.
6 calculators
Time Conversions
Convert between time units — seconds, minutes, hours, days, weeks, months, years. Enter any duration — see all equivalent time units. Free.
12 calculators
Time Calculators
View allHours Calculator
Add and subtract hours and minutes for scheduling. Enter time values — see total duration with decimal hours conversion. Free.
Hours & Minutes Calculator
Perform time arithmetic with hours and minutes. Enter your times — see the total with AM/PM format and decimal conversion. Free.
Time Calculator
Add, subtract, multiply, and divide time values. Enter your hours and minutes — see the result with decimal conversion. Free.
Work Hours Calculator
Calculate total work hours for any period. Enter start and end times with breaks — see regular hours, overtime, and weekly totals. Free.
Countdown Timer
Count down to any future date or event. Enter the target date — see days, hours, minutes, and seconds remaining. Free.
Stopwatch Timer
Use a digital stopwatch with lap tracking. Enter laps — see split times, total time, and fastest/slowest lap comparison. Free.
Date Calculators
View allAge Calculator
Calculate exact age in years, months, days, hours, and minutes. Enter date of birth — see your precise age and next birthday. Free.
Date Difference Calculator
Calculate the exact number of days, weeks, and months between two dates. Enter start and end date — see all units with weekday count. Free.
Date Calculator
Add or subtract days, weeks, or months from any date. Enter a date and duration — see the resulting date with day of week. Free.
Days & Business Days
Count days between dates with business days option. Enter start and end dates — see total days, business days, and weekends. Free.
Day of the Week
Find the day of the week for any date in history or the future. Enter the date — see day name, day number, week number, and calendar facts. Free.
How Old Am I?
Calculate your exact age in years, months, days, hours, and minutes. Enter date of birth — see precise age with next birthday countdown. Free.
Time Conversions
View allTime to Decimal
Convert time in hours and minutes to decimal hours. Enter HH:MM — see decimal hours for timesheet, billing, and payroll calculations. Free.
Decimal to Time
Convert decimal hours to hours and minutes. Enter decimal time (e.g. 2.75) — see HH:MM format for timesheets and billing. Free.
Military Time Converter
Convert between 12-hour and 24-hour (military) time. Enter either format — see the other with AM/PM and 24h equivalents. Free.
Hours to Minutes
Convert hours to total minutes. Fast and accurate result with formula, step-by-step method and unit overview. Free tool.
ISO Week Number Calculator
Find the ISO 8601 week number for any date. Enter your date — see week number, year, and first/last day of that week. Free.
Quarter of Year Calculator
Find which fiscal or calendar quarter any date falls in. Enter your date — see quarter number, Q start/end dates, and days remaining. Free.