Created by Browserling
With this browser-based application, you can check if a calendar date exists and is correct. It tests if the date (and optional time) is well-formatted and also analyzes the limits of each date component. You can validate as many calendar dates as you want, choose the date status format, and print a descriptive error message. Created by computer nerds from team Browserling.
This is a quick online utility for validating calendar dates. The date validation algorithm that we implemented checks the format of a date, the components of a date, and verifies the date exists (for example, a leap year exists only once every 4 years). Once the validation is complete, it displays the result of the test on the screen. If the date is correct, the tool prints "Date is valid" (or just "Valid" if the short message form is enabled). If the date is incorrect, the tool prints "Date is invalid" (or "Invalid" in the short form). The first thing the program checks is that the date has a correct format and that all parts of the date contain only numbers. A valid full date format is "YYYY-MM-DD hh:mm:ss", however it can also be shortened to "YYYY-MM-DD hh:mm", "YYYY-MM-DD hh", "YYYY-MM-DD", "YYYY-MM", or just "YYYY". The program then checks each date component individually. The year must be at least -271821 (which is 271821 BC) and must not exceed 275760 (AC). For months, valid values are from 1 to 12. The dates in each month may differ, some months have 28 days, some 29, some 30, and some 31. The program checks the number of days in each month separately and displays an error if the number of days in that month are exceeded. If the input date has a clock time part, then it's also run through a number of checks. In particular, the maximum time is limited to 24:00:00, the minutes must not exceed 59m, and the seconds must not exceed 59s. To validate multiple calendar dates, enter them one per line into the input field. To get a shortened status check result use the "Short Status" checkbox option and to display a detailed description of the date error, use the checkbox "Show Detailed Error". Timeabulous!
This example verifies two calendar dates. It checks the year, month, and date of each date and prints the result to the output text area. The first date is valid but the second date is invalid because there are a maximum of 12 months in a year but the date has "13" in the month component.
In this example, we enter many calendar dates as the input and quickly analyze the validity of all dates. We also activate the verbose error option so that we can instantly find and fix errors in calendar dates.
In this example, we catch all the incorrect dates in a long list of dates. We use the short status output format and also add a short error description in parentheses to each invalid date.
You can pass input to this tool via ?input query argument and it will automatically compute output. Here's how to type it in your browser's address bar. Click to try!
Quickly visualize your life in weeks or months.
Quickly draw a wall clock that shows a particular time.
Quickly draw an electronic clock that shows a particular time.
Quickly draw a monthly calendar for any month of the year.
Quickly print a list of neat-looking clock times (such as 10:11:12).
Quickly print a list of neat-looking calendar dates (such as 2055-05-05).
Quickly print a list of symmetric clock times (such as 05:22:50).
Quickly print a list of symmetric dates (such as 2020-02-02).
Quickly convert clock time in H:M:S format to seconds.
Quickly convert seconds to clock time in H:M:S format.
Quickly convert time in 24 hour format to 12 hour format.
Quickly convert time in 12 hour format to 24 hour format.
Quickly find how many seconds have passed since midnight.
Quickly find how many seconds are left till midnight.
Quickly find the difference between two clock times.
Quickly find the difference between two calendar dates.
Quickly find the age difference between two or more people.
Quickly add hours, minutes, and seconds to the given time.
Quickly subtract hours, minutes, and seconds from the given time.
Quickly add days, months, and years to the given date.
Quickly subtract days, months, and years to from the given date.
Quickly change the current time format to any new format.
Quickly change the current date format to any new format.
Quickly round the given clock time up or down.
Quickly round the given calendar date up or down.
Quickly drop seconds and minutes from a clock time.
Quickly drop days and months from a calendar date.
Quickly sort clock times in ascending or descending order.
Quickly sort calendar dates in ascending or descending order.
Quickly sort time intervals by their start time or length.
Quickly sort date intervals by their start date or length.
Quickly check if the given clock time is valid.
Quickly check if the given calendar date is valid.
Quickly find how many hours are in the given days.
Quickly find how many days are in the given hours.
Quickly find the astrological sign by the birthday or any date.
Quickly print a list of the dates of all astrological signs.
Quickly find the average value of multiple clock times.
Quickly find the average value of multiple calendar dates.
Quickly generate a list of random clock times.
Quickly generate a list of random calendar dates.
Quickly create a list of clock times that match your criteria.
Quickly generate a list of calendar dates that match your criteria.
Quickly split the given time period into multiple intervals.
Quickly split the given date period into multiple intervals.
Quickly generate increasing or decreasing clock times.
Quickly generate increasing or decreasing calendar dates.
Quickly print a list of all leap years.
Quickly print a list of all common years.
Quickly test if the given year is a leap year.
Quickly test if the given year is a common year.
Quickly find how old a cat would be if it was a human.
Quickly find how old a human would be if he/she was a cat.
Quickly find how old a dog would be if it was a human.
Quickly find how old a human would be if it was a dog.
Quickly convert a modern Gregorian date to a Julian date.
Quickly convert an ancient Julian date to a Gregorian date.
Quickly calculate the Julian day number for any calendar date.
Quickly convert the Julian day to a regular calendar date.
Quickly print a list of all Easter dates for all years.
Quickly convert a UNIX Epoch time to a human-readable time.
Quickly convert human-readable time to a UNIX Epoch time.
Quickly generate increasing or decreasing UNIX timestamps.
Quickly generate one or more random UNIX Epoch times.
Quickly convert a HH:MM:SS clock to a military HHMM clock.
Quickly convert a military clock HHMM to a HH:MM:SS clock.
Quickly write a clock time in text format (as English text).
Quickly write a calendar date in text format (as English text).
Quickly add slight perturbations to the given clock times.
Quickly add slight perturbations to the given calendar dates.
Quickly find what day of the week the given calendar date falls on.
Quickly find what day of the year the given calendar date falls on.
Quickly find what week of the year the given calendar date falls on.
Quickly calculate the calendar date from a day number of a year.
Quickly find the angle between the hour hand and minute hand.
Quickly print a list of all clock times with a specific hand angle.
Quickly print all dates when a specific day happens.
Quickly find all Fridays that fall on the 13th day of the month.
Quickly create a list of all Independence Day dates.
Quickly create a list of all Christmas Day dates.
Quickly create a list of all New Year dates.
Quickly create a list of all Thanksgiving dates.
Quickly show useful information about a particular clock time.
Quickly show useful information about a particular calendar date.
Quickly draw a timeline of multiple time intervals.
Quickly draw a visualization of multiple date intervals.
Quickly find the time a clock shows if you look at it in a mirror.
Quickly convert time and date from one timezone to another.
Quickly convert time and date from one country to another.
Quickly print the season (winter, spring, summer, autumn) by date.
Draw a binary clock that shows time in base two.
Draw a clock in Salvador Dali style showing custom time.
Draw a weird-looking clock that shows a particular time.
Draw a π clock with π hours in a day.
Draw a 360° clock with 360 degrees in a day.
Create a GIF animation of an analog clock.
Create a GIF animation of a digital clock.
Create a GIF animation of a clock that's broken.
Draw a daily calendar for a single day.
Draw a weekly calendar for any week of the month.
Draw a yearly calendar for the entire year.
Draw a calendar that shows moon phases.
Draw a calendar that shows the seasons and Sun's position.
Draw a calendar that shows when the Sun rises and sets.
Draw a calendar that shows when the Moon rises and sets.
Draw an animation that counts down (or up) time.
Create a GIF animation of a sand clock.
Animate a timeless clock that goes in an infinite spiral.
Visualize the given clock time as a pie chart.
Visualize the current year as a pie chart.
Visualize the given clock time as a bar chart.
Visualize the current year as a bar chart.
Visualize the given clock time as a pixel wall (1px = 1sec).
Visualize the current year as a pixel wall (1px = 1day).
Visualize the given clock time as bubbles.
Visualize the current year as bubbles.
Visualize the given clock time as an arrow.
Quickly calculate time passed and left in the current day as pct.
Quickly calculate time passed and left in the current year as pct.
Convert regular clock time to binary clock time (bintime).
Quickly regular calendar date to binary date (bindate).
Convert regular clock time to decimal clock time (dectime).
Quickly regular calendar date to decimal date (decdate).
Convert regular clock time to hexadecimal time (hextime).
Quickly regular calendar date to hexadecimal date (hexdate).
Create a GIF animation of the Moon for a particular month.
Create an animation of the Moon orbiting the Earth.
Create a 88 day animation of the Mercury orbiting the Sun.
Create a 225 day animation of the Venus orbiting the Sun.
Create a 365 day animation of the Earth orbiting the Sun.
Create a 687 day animation of the Mars orbiting the Sun.
Create a 4,330 day animation of the Jupiter orbiting the Sun.
Create a 10,756 day animation of the Saturn orbiting the Sun.
Create a 30,687 day animation of the Uranus orbiting the Sun.
Create a 60,190 day animation of the Neptune orbiting the Sun.
Create a 90,560 day animation of the Pluto orbiting the Sun.
Create an animation of all planets in the Solar System.
Create an animation of Phobos and Deimos orbiting Mars.
Animate Io, Europa, Ganymede, Callisto orbiting Jupiter.
Animate Titan, Rhea, Iapetus, Enceladus orbiting Saturn.
Animate Titania, Oberon, Umbriel, Ariel, Miranda orbiting Uranus.
Animate Triton, Nereid, and Proteus orbiting Neptune.
Animate Charon, Nix, Hydra, Kerberos, Styx orbiting Pluto.
Find dates when two or more planets align in a straight line.
Find dates when the solar eclipse happens.
Find dates when the lunar eclipse happens.
Calculate your age based on the orbital period of other planets.
Represent a clock time as a matrix.
Represent a calendar date as a matrix.
Represent a clock time as a vector.
Represent a calendar date as a vector.
Draw a time series chart.
Given a bunch of time intervals, find overlapping intervals.
Generate a bunch of overlapping time intervals.
Generate a bunch of non-overlapping time intervals.
Generate random clock time intervals.
Given a bunch of date intervals, find overlapping intervals.
Generate a bunch of overlapping date intervals.
Generate a bunch of non-overlapping date intervals.
Generate random calendar date intervals.
Swap a clock's hour hand with minute hand.
Find the reverse of the given clock time.
Find the inverse of the given clock time.
Shift the given clock time by any time interval.
Change the clock scale from 24 hours to any other hours.
Generate a list of valid clock times (for testing).
Generate a list of invalid clock times (for testing).
Generate a list of valid calendar dates (for testing).
Generate a list of invalid calendar dates (for testing).
Create errors in the given clock times (for testing).
Create errors in the given calendar dates (for testing).
Convert a calendar date to seconds.
Convert seconds to a calendar date.
Create a crontab expression from human language.
Rewrite a crontab entry into human language.
Quickly find the week of the month of a calendar date.
Quickly find how many days have passed since start of the year.
Quickly find how many days are left till the end of the year.
Quickly find how many days are left till a specific date.
Find how many minutes are in the given seconds.
Find how many hours are in the given seconds.
Find how many days are in the given seconds.
Find how many weeks are in the given seconds.
Find how many months are in the given seconds.
Find how many years are in the given seconds.
Find how many seconds are in the given minutes.
Find how many hours are in the given minutes.
Find how many days are in the given minutes.
Find how many weeks are in the given minutes.
Find how many months are in the given minutes.
Find how many years are in the given minutes.
Find how many seconds are in the given hours.
Find how many minutes are in the given hours.
Find how many weeks are in the given hours.
Find how many months are in the given hours.
Find how many years are in the given hours.
Find how many seconds are in the given days.
Find how many minutes are in the given days.
Find how many weeks are in the given days.
Find how many months are in the given days.
Find how many years are in the given days.
Find how many seconds are in the given weeks.
Find how many minutes are in the given weeks.
Find how many hours are in the given weeks.
Find how many days are in the given weeks.
Find how many months are in the given weeks.
Find how many years are in the given weeks.
Find how many seconds are in the given months.
Find how many minutes are in the given months.
Find how many hours are in the given months.
Find how many days are in the given months.
Find how many weeks are in the given months.
Find how many years are in the given months.
Find how many seconds are in the given years.
Find how many minutes are in the given years.
Find how many hours are in the given years.
Find how many days are in the given years.
Find how many weeks are in the given years.
Find how many months are in the given years.
Find how old a human would be if he/she was a bird.
Find how old a bird would be if it was a human.
Convert clock time on Earth to clock time on Mars.
Convert clock time on Mars to clock time on Earth.
Convert Earth time to Star Trek's stardate.
Convert Star Trek's stardate to Earth time.
Print a list of clock times with hours equal mins equal secs.
Print a list of calendar dates with years equal months equal days.
Print a list of all clock times when hands are in a straight line.
Given clock times in various formats, convert them to one format.
Given calendar dates in various formats, make them the same format.
Cyclically shift HH, MM, SS time parts to the left or right.
Cyclically shift YYYY, MM, DD date parts to the left or right.
Perform freeform clock time arithmetics.
Perform freeform calendar date arithmetics.
Find the sum of hours plus minutes plus seconds.
Find the sum of years plus months plus days.
Find clock hand position so that hr + min + sec equals your value.
Find calendar date so that year + months + day equals your value.
Print all clock icons from 00:00 to 24:00.
Generate date and time that only Zalgo can understand.
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