Age calculator
For age or a calendar interval between a starting and selected date.
10 tools
Date and time calculators
Date calculators help find exact age and count business days between dates. They are useful for forms, planning, deadlines and quick calendar checks.
All in section
All calculators Date and time
Age calculator
Calculate exact age in years, months and days.
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Date and time
Business days calculator
Count business days between two dates with optional excluded dates.
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Date and time
Date calculator
Find the date a number of days, weeks, months or years from a start date.
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Date and time
Day of the week calculator
Which day of the week a date falls on.
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Date and time
Leap year calculator
Check whether a year is a leap year and find the nearest ones.
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Date and time
Sleep time calculator
Wake-up time or bedtime using assumed 90-minute blocks.
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Date and time
Time duration calculator
Duration between two times, or a time shifted by a duration.
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Date and time
Time zone difference calculator
Convert a time between two UTC offsets, midnight rollover included.
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Date and time
Week number calculator
ISO week and ordinal day for a valid Gregorian date.
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Date and time
Work hours calculator
Hours over a period from shift start and end with a break, night shifts included.
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Which calculation to choose
Date calculator
For a date a specified number of calendar days before or after a starting date.
What to prepare
Check both dates, shift direction and boundary-inclusion rules. Working-day deadlines require an applicable calendar separately.
Common mistake
A calendar day is not a working day. Page language does not select a holiday jurisdiction or a legal deadline.
Popular calculators
FAQ
Are leap years handled?
Yes. Date calculations use calendar dates and account for leap years.
Can I count holidays?
The business days calculator lets you add excluded dates manually.
Can I calculate age for a future date?
Yes. Change the target date to estimate age on a specific day.
Categories
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Loan, mortgage, compound interest, percentage and discount calculators for everyday money decisions.
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Currency converter and popular pairs for quick travel, shopping and budget estimates.
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Convert length, mass, temperature, pressure and other quantities between units.
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Current, voltage, resistance, power and circuit supply.
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Test percentages, the grade you need and reading speed.
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Area, perimeter, volume and surface of flat and solid shapes.
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Force, energy, work, power and motion with stated units and models.
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Concentration, moles, dilution, pH and the ideal gas law.