Do the calculators work without the internet?

All of them count in your browser. Only the working-days calculator asks the server for the public holidays of the country you pick.

How are months counted?

By the calendar, not by an average of 30.44 days: one month after 31 January is 28 February, and the calculators say exactly that.

Are there pages for particular dates?

Yes, for birth years: a page for every year from 1900 tells you how old you are now. Other dates are answered by the date pages of this site.

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Date Calculators

Eight calculators for dates and time zones: the gap between two dates, working days, age, adding days, and a meeting hour that suits every city.

Add days to a date, count the days between two dates, find your exact age, or work out when to go to bed. Every date calculator on this site is gathered on this page, free and running in your browser.

Date difference

Date DifferenceHow much time lies between two dates — in days, weeks, months and years. Working DaysWorking days between two dates, with weekends and public holidays taken out. Days Until a DateHow many days are left until a date you choose. Days Since a DateHow many days have passed since a date you choose.

Age and birthday

Age CalculatorExact age in years, months and days — and the next birthday.

Adding and subtracting dates

Add or Subtract DaysAdd or take away days, weeks, months or years from a date.

Time zones

Time Zone ConverterThe same moment in two time zones, daylight saving included. Meeting PlannerA working hour that suits every city on the list.

Date infoEverything about one date Holidays by countryOfficial days off CountdownsDays until events World clockTime around the world

How to use Date Calculators

Pick the tool that matches your question from the list below. Enter your dates — today is filled in for you, written in mm/dd/yyyy order. Read the result and adjust the inputs until the tool answers the question you actually meant.

What lives on this page

Days between dates — how many days, weeks or months separate two points on the calendar. Add or subtract days — where does a 90-day deadline actually land, weekends included. Age calculator — exact age in years, months and days from any date of birth.

Sleep calculator — counts backward from your wake-up time so you go to bed at a sensible hour. Work hours — a free time clock calculator online for adding up shifts across a week. Time zone converter — line up UTC against Los Angeles, New York or anywhere else in the USA and beyond. Sunrise and sunset times — when the light arrives and leaves on any given day.

What a date calculator answers

The everyday questions: which day of the week you were born, what date is forty-five days before the wedding, which week of the year it is right now, how many working hours are left in the month. None of it is hard arithmetic — it is just arithmetic that fingers are bad at once a month boundary gets involved.

One question answers itself here: if you searched "what is the date today in mm/dd/yyyy", the top of this page shows the current date in exactly that format the moment it loads. Counting days on your fingers works fine until the month ends. Then the fingers need a calculator too.

Free time clock calculator for hours worked

A free time clock calculator online adds up worked hours from clock-in and clock-out times, including shifts that cross midnight, and converts minutes to decimal hours for payroll. If you have ever added 7:50 and 6:25 by hand, you know why this exists: time is base 60, wages are base 10, and the two do not mix in your head at five on a Friday.

Anyone who has counted days on their knuckles, twice, and gotten two different answers, already understands date calculators.

Getting a result you can defend

Write down the two dates in full, with the year, before you type anything. Decide whether the start day counts as day zero or day one, and say which in whatever you send. Check whether the span crosses a February, and whether that year is a leap year.

Sanity-check the answer against something you already know — roughly fifty-two weeks to a year, roughly thirty days to a month.

Questions and answers

What is today's date and the day of the week?: Look at the header of this page — the current date and the weekday are displayed live, which beats any written answer that goes stale overnight.
Are these tools free?: Yes. Each one is a free date calculator in the plain sense: no account, no trial, no limit on how often you use it.
Where is the random number generator?: On the Generator page. If you were looking for the calculator.net random number generator, the one here does the same job — pick a range, get an integer — without leaving this site.