Time tools

Time tools measure an interval, count down, add days to a date, or tell you the weekday of a date you type. The stopwatch and countdown run on this page; they are not a phone timer.

Use the stopwatch when you need laps at the computer, the countdown for a fixed block of work, and the date tools when the question is a calendar span rather than a running clock.

A countdown stops if you close the tab. Date answers use your device clock and its timezone, so a wrong clock gives a wrong weekday.

Time tools in this category

14 tools

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Age Calculator — How Old Am I?

Exact age from a birth date to today, in years, months and days, plus days until the next birthday. For age on a past test date use Chronological Age; to turn an age into a birth year use Birth Year.

Use this tool when Find your exact age in years, months and days for official forms, insurance or medical questionnaires.

Exact age in years, months and days with leap years handled correctly.
Total full months, weeks and days lived since birth.
Next birthday date, days remaining, and the age you will turn.

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Online Alarm Clock

Set a wake-up time and get a live countdown, a looping generated melody, a full-screen notice and a blinking tab title when the moment arrives — right in the browser tab.

Use this tool when Need a wake-up alarm on a laptop because your phone is dead, lost or charging in another room?

HH:MM time input with automatic today/tomorrow targeting and a live hours:minutes:seconds countdown.
Looping WebAudio melody re-signalled every 30 seconds until Stop — generated, not an audio file.
Full-screen wake-up notice, blinking document title and a countdown mirrored into the tab title.

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Business Days Calculator

Count weekdays between two dates, skipping Saturdays, Sundays, and any holiday dates you paste.

Use this tool when Estimating a delivery or response deadline in working days?

Inclusive or exclusive start and end
Holiday list split on spaces, commas, or semicolons
A calendar-day gap beside the business-day count

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Monthly Calendar Generator

Draw one Gregorian month as a seven-column grid, starting the week on Monday or Sunday, and print that grid.

Use this tool when Need a clean monthly calendar to print for notes or shift planning?

Leading blank cells before day 1
Weekday names in the page language
No event list and no multi-month sheet

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Countdown Timer

Count down from the minutes and seconds you set, and play a short tone at zero.

Use this tool when Need to block out 25 minutes for a Pomodoro session?

Minutes and seconds, displayed as MM:SS with no hour field
Pause keeps the remaining time. Reset reloads the boxes.
A duration of zero does not start

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Add or Subtract Dates

Move a calendar date forward or backward by a chosen number of days, weeks, months, or years.

Use this tool when Calculating a due date a fixed number of days or months from today?

Add or subtract calendar units
Days, weeks, months, and years
End-of-month-safe arithmetic

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Day of the Week Calculator

Name the weekday of a calendar date and give its day-of-year number and how many days remain after it.

Use this tool when Curious which weekday a birthday or historical event occurred on?

UTC calendar dates only
Leap years change the day count after February
No time of day and no time zone conversion

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Pomodoro Timer

Stay focused with timed work sessions and automatic short and long breaks, complete with a gentle beep and a live countdown in the tab title.

Use this tool when Run classic 25/5 pomodoro cycles while studying, with the tab-title countdown visible from your notes app.

Adjustable work, short-break and long-break durations plus a configurable long-break interval.
Large time display with the current session type and a completed-pomodoros counter.
Subtle WebAudio beep on every phase change — no audio files, no volume spikes.

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Stopwatch

Start, pause, and lap a clock that reads elapsed time from performance.now and paints hundredths of a second.

Use this tool when Do you need to track the time of a sports circuit or a set of exercises?

Start and pause on the same button
Lap times listed newest first
Hundredths of a second, with minutes allowed to pass 59

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Time Duration Calculator

Hours and minutes between two clock times — overnight included — plus adding or subtracting hh:mm durations.

Use this tool when Find out exactly how long a shift lasts: pick the start and end times, subtract the lunch break, and read the result in hh:mm and decimal hours.

Time between two clock times with optional break
Add or subtract two hh:mm durations
Results in hh:mm, decimal hours, and minutes

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