This regex validates dates in YYYY-MM-DD format with comprehensive rules: Year: Must be greater than 1900 (1901-9999) Month: Valid range 01-12 Day: Validates correct number of days per month: 31 days: January, March, May, July, August, October, December 30 days: April, June, September, November 28 days: February (non-leap years) 29 days: February 29th only in leap years The regex captures year, month, and day in separate groups (positions vary based on which alternative matches).

This expression validates any YYMMDD date, and insures that the leap year is accounted for. This is valid till 2099, 2100 is NOT a leap year.

UUID v7 Resources: https://uuid7.com/ https://uuid.ramsey.dev/en/stable/rfc4122/version7.html https://www.ietf.org/archive/id/draft-peabody-dispatch-new-uuid-format-04.html#name-uuid-version-7 "UUID version 7 features a time-ordered value field derived from the widely implemented and well known Unix Epoch timestamp source, the number of milliseconds seconds since midnight 1 Jan 1970 UTC, leap seconds excluded. As well as improved entropy characteristics over versions 1 or 6." Source IETF

1000-9999 years '-', ' ', ':', '.', or '/' may be user as divider

Not only validates valid date/time, but also the number of days in a month (including leap year), and both Z and UTC offset.

Handles many nuanced cases around time zone offsets, leap seconds and leap days. References: List of UTC Offsets RFC 3339, the stricter rules that most systems use in practice ISO 8601, the widely known name for this format Leap Year Leap Second Caveats: Rejects -00:00 timezone offset. rejects all future leap seconds, and only parses ones with a 'Z' offsets. Pattern (?= (?:^ (?: # All non-leap-second YYYY-MM-DD parts: \d\d\d\d-(?:01-9] |10|11|12)-(?:0[1-9]|1[0-9]|2[0-8]) # Days 01-28 | \d\d\d\d-(?:0[13-9] |10|11|12)-(?:29|30) # Days 29+30 | \d\d\d\d-(?:0[13578]|10 |12)-31 # Day 31 | (?:\d\d[2468|\d\d048]|\d\d[13579)-02-29 # leap years not divisible by 100 | (?:0246800|1357900)-02-29 # leap years divisible by 400 ) T (?:(?:00-9]|1[0-9]|2[0-3]):(?:[0-5):(?:0-5)) # time part (?:\.\d\d\d)? # ms part (optional) (?:Z|\+\-|1[012]):00|\+0[34569]:30|\+10:30|-0[39]:30|\+1[34]:00|\+0[58]:45|\+12:45) $) |^(?:1972 |198[1235]|199[2347]|2012|2015 )-06-30T23:59:60Z$ # all june leapsecs |^(?:197[2-9]|1987|1989|199[058] |2005|2008|2016)-12-31T23:59:60Z$ # all december leapsecs ) (?!.*-00:00$) # if given a -00:00 offset reject unconditionally, psychhhh OK! Since only valid times are now possible, we can use a loose pattern match to parse. ^(\d\d\d\d)-(\d\d)-(\d\d)T(\d\d):(\d\d):(\d\d)(?:\.(\d\d\d))?((Z)|([\+\-])(\d\d):(\d\d))$ Test cases // accept: Exemplars 2008-02-03T04:05:06.007Z 2008-02-03T04:05:06Z 0000-01-01T00:00:00.000Z 9999-12-31T59:59:59.999Z 9999-12-31T59:59:59Z 2008-02-03T04:05:06.007+12:45 2008-02-03T04:05:06+03:30 0000-01-01T00:00:00.007-09:30 0000-02-29T04:05:06.007+14:00 9999-12-31T23:59:59.999+12:00 9999-12-31T23:59:59-12:00 // accept: Leap day, year is multiple of four 0004-02-29T04:05:06Z 0096-02-29T04:05:06Z 1560-02-29T04:05:06Z 2004-02-29T04:05:06Z 2020-02-29T04:05:06Z 2032-02-29T04:05:06Z 9996-02-29T04:05:06Z // accept: Leap day, year is Multiple of 400 0000-02-29T04:05:06Z 1200-02-29T04:05:06Z 1600-02-29T04:05:06Z 2000-02-29T04:05:06Z 3600-02-29T04:05:06Z 8000-02-29T04:05:06Z 9600-02-29T04:05:06Z // accept: Day in range for month 2008-01-30T04:05:06Z 2008-03-30T04:05:06Z 2008-04-30T04:05:06Z 2008-05-30T04:05:06Z 2008-06-30T04:05:06Z 2008-07-30T04:05:06Z 2008-08-30T04:05:06Z 2008-09-30T04:05:06Z 2008-10-30T04:05:06Z 2008-11-30T04:05:06Z 2008-12-30T04:05:06Z 2008-01-31T04:05:06Z 2008-02-31T04:05:06Z 2008-03-31T04:05:06Z 2008-05-31T04:05:06Z 2008-07-31T04:05:06Z 2008-08-31T04:05:06Z 2008-10-31T04:05:06Z 2008-12-31T04:05:06Z // accept: leap second 1972-06-30T23:59:60Z 1981-06-30T23:59:60Z 1982-06-30T23:59:60Z 1983-06-30T23:59:60Z 1985-06-30T23:59:60Z 1992-06-30T23:59:60Z 1993-06-30T23:59:60Z 1994-06-30T23:59:60Z 1997-06-30T23:59:60Z 2012-06-30T23:59:60Z 2015-06-30T23:59:60Z 1972-12-31T23:59:60Z 1973-12-31T23:59:60Z 1974-12-31T23:59:60Z 1975-12-31T23:59:60Z 1976-12-31T23:59:60Z 1977-12-31T23:59:60Z 1978-12-31T23:59:60Z 1979-12-31T23:59:60Z 1987-12-31T23:59:60Z 1989-12-31T23:59:60Z 1990-12-31T23:59:60Z 1995-12-31T23:59:60Z 1998-12-31T23:59:60Z 2005-12-31T23:59:60Z 2008-12-31T23:59:60Z 2016-12-31T23:59:60Z // REJECT: Out of range 10000-02-29T04:05:06Z 2008-00-30T04:05:06Z 2008-13-30T04:05:06Z 2008-02-30T04:05:06Z 2008-04-31T04:05:06Z 2008-06-31T04:05:06Z 2008-09-31T04:05:06Z 2008-11-31T04:05:06Z 2008-12-32T04:05:06Z 2008-12-99T04:05:06Z 2008-12-00T04:05:06Z // REJECT: Hour/min/sec out of range 2008-12-08T60:05:06Z 2008-12-08T04:60:06Z 2008-12-08T04:99:06Z 9999-12-31T59:59:61.999Z 2008-02-03T04:05:61.999Z 2008-02-03T04:05:61Z // REJECT: Negative dates not accepted -2000-02-29T04:05:06Z // REJECT: Malformed 2008-02-0304:05:06Z 20080203T040506Z 2008-02-03T04:05:06007Z 2008-02-03T04:05:06.7Z 2008-02-03T04:05:06.07Z 2008-02-03T04:05:06.0007Z 2008-02-03T04:05:06 2008-02-03T04:05:06.Z // REJECT: no leap second 1978-06-30T23:59:60Z // REJECT: assumes no future leap seconds 2024-12-31T23:59:60Z 2099-12-31T23:59:60Z 9999-12-31T23:59:60Z // REJECT: leap seconds only in UTC format 2005-12-31T23:59:60+00:00 2008-12-31T23:59:60+00:00 // REJECT: Not a leap day, not a multiple of four 2003-02-29T04:05:06Z 2037-02-29T04:05:06Z 2038-02-29T04:05:06Z 2039-02-29T04:05:06Z 9997-02-29T04:05:06Z 9998-02-29T04:05:06Z 9999-02-29T04:05:06Z // REJECT: Not a leap day, mult of 100 0100-02-29T04:05:06Z 1000-02-29T04:05:06Z 2100-02-29T04:05:06Z 2200-02-29T04:05:06Z 3500-02-29T04:05:06Z 3700-02-29T04:05:06Z

This will match all four-digit years that are leap years, using the "either (multiple of four but not a multiple of 100) OR (multiple of 400)" rule. Explained / ^( \d\d2468|\d\d13579|\d\d048]| # multiple of four but not 100 [0246800 |1357900 # multiple of four hundred )$ /gmx References Leap Year RFC 3339, the stricter rules that most systems use in practice ISO 8601, the widely known name for this format Test Cases // accept: multiple of four () 0004 0008 0012 0016 0020 0024 0028 0032 0036 0040 0044 0048 0052 0056 0060 0064 0068 0072 0076 0080 0084 0088 0092 0096 1560 2004 2008 2012 2016 2020 2024 2028 2032 2036 2040 2044 9996 // accept: Multiple of 400 0000 0400 0800 1200 1600 2000 2400 2800 3200 3600 4000 4400 4800 5200 5600 6000 6400 6800 7200 7600 8000 8400 8800 9200 9600 // REJECT: Not a multiple of four 0101 0102 0103 1537 1538 2001 2002 2003 2021 2022 2023 2025 2026 2027 2029 2030 2031 2033 2034 2035 2037 2038 2039 2041 2042 2043 9997 9998 9999 // REJECT: Multiple of 100 but not 400 0100 0200 0300 0500 0600 0700 0900 1000 1100 1500 2100 2200 2300 2500 2600 2700 2900 3000 3100 3300 3400 3500 3700 // REJECT: Negative dates not accepted (malformed) -2000 -0400 -0100 -0004 // REJECT: Out of range date per RFC 3339 10000

Accepting every date between 2010 to 2050. Format is YYYY-MM-DD hh:mm

Source: https://stackoverflow.com/questions/8647893/regular-expression-leap-years-and-more Seems to be valid for 1800 through 2099. Requires leading zeros. Matches MM/DD/YYYY format only.

Very simple validation expression that will validate a date in the range of 19000101 through 20991231. These formats are very popular for partitioning and representing dates as Long values or Integers. This does not check for Leap year values, or the months with varying number of days. Please Note: this will return a match on 20220231 even though this is not a valid date. Additional validations should be used if Leap years and Days of the Month should be verified as well.

A fully tested regex that extracts and validates date parts using named capturing groups. \ Validations: Year must be preceded by nothing or a non-digit character Year must have 4 digits Month must be between 01 and 12 Month must have 2 digits Day must be between 01 and the maximum number of days for the month (e.g. february can't have more than 29 days) Day must have 2 digits Day must be followed by nothing or a non-digit character Separator must be any single character that is not a space or an alphanumeric character Separator must be the same between each date part \ Capturing groups: | # | Name | Description | |:-:|:-------:|-------------------------------------| | 1 | year | 4 digits of the year | | 2 | sep | Date parts separator | | 3 | month | 2 digits of the month | | 4 | day | 2 digits of the date (day of month) | \ Example usage: let match = regex.exec('2020-11-22') console.log('year: %s, month: %s, day: %s', match.groups.year, match.groups.month, match.groups.day) // year: 2020, month: 11, day: 22 \ Compatibility: (updated 2020-11-20) Chrome >= 64 Edge >= 79 Firefox >= 78 IE incompatible (lookbehind assertions & named capture groups not supported) Opera >= 51 Safari incompatible (lookbehind assertions not supported) NodeJS >= 10.0.0 See regex compatibility table. \ Note: does not validate leap years (not really possible in regex)

/((20)0-9]{2}[-|102])[-|12|301]))|((20)[0-9]{2}[-|11)-|12|30))|((20)0-9]{2}[--|10-9]|2[0-8]))|((((20)(04|08|[2468|13579))|2000)-[-]29)/g

This regex validates all dates between 01/01/1900 and 12/31/2099, including leap-year validation. It follows a mm/dd/yyyy format, and enforces two-digit month/year formats.

This regex validates all dates between 1/1/1900 and 12/31/2099, including leap-year dates. It allows either one or two digit month/date values.

Date regex with leap years

2018/08/14

Format of 29Feb2020 or 29FEB2020 with leap year check

Validate dates in the format of 20201231 with leap year check on the 29th of February

Validate dates in the formats of 1Feb20/01Feb20/29FEB20 with the 29th of February invalid on non-leap years.

Matches dates in the following format: %Y/%m/%dT%H:%M:%S This is 24h format (00-23h) and no leap seconds.

Matches dates in the following format: %Y/%m/%dT%H:%M:%S This is 24h format (00-23h) and no leap seconds.

Validate date in format DD/MM/YYYY HH:mm generaly used in Brazil. With hour in 24 hours format and validating leap year too, optional time.

with Leap Year support (dd/MM/yyyy)

Following inputs are accepted dd.mm.yyyy while 29.02.2016 accepted, 29.02.2017 is not. also some months last days should be 30, not 31 ex: 31.11.2016 not accepted

Regex following "ISO 8601" without hour : allowing only month 1 to 12, the day of 1 to 31 for the months of 31 days, the months from 1 to 30 for the months of 30 days, the day of 1 to 28 for February, and the day from 1 to 29 for February of leap years

1900 - 2015. Useful for Birthdates

12.04.1975T03:02:00.88 With milliseconds and T seperator. Excludes most invalid dates, except 30/31ths of month, leap years/february heaving only 29/28.

Matches an ISO8601 date time string, including fractional time. Does not exclude non-existent times (such as the 29th february in non-leap-years)

Validates DateTime of format YYYYMMDDhhmmss including Leap Year

this regex is able to validate a date (format dd.mm.yyyy) in every state of user typing. i use it to ensure that the user isn't able to type in an invalid date at all (except from a leap year check which is done afterwards) The regex also makes assumptions of 'missed' separators so 1234 is captured in groups which can then be transformed to \1.\2.\3 -> 12.3.4 It was intensively but not exhaustivly tested

This pattern validates all the possible dates for all months in YYYY-MM-DD format. Due to limitations of regex it can not validate the dates of february for leap year. It will allow the date 29 for leap year too. Make sure to validate that yourself.

Date Validation with leap year handling, & it takes care of date validation in the format like :mm/dd/yyyy or mmddyyyy or mm-dd-yyyy or m/d/yyyy or m-d-yyyy. 12/01/1986 02/29/2016 02/29/2015 13/31/1986 12/31/1980 1/32/2015 1/31/2015 01012016 01/01/2016 1/1/2016 1/1/16 01/01/16 01-01-2016 1-1-2016 1-1-16 01-01-16

Besides leap year handling, this takes care of date validation in the yy-mm-dd format.

Regular expression for asp:RegularExpressionValidator with format MMddyy. i have resolved the issue for leap Year and month ending day as well.

Regular expression for asp:RegularExpressionValidator with format MMddyy. i have Resolved leap year issue as well as month ending day issue with Regular expression

improved "Ahmed Z" regexp. PHP date format (and input[type=text] format date too): YYYY-MM-DD. Year between [1900-2099]. No leap year check. Month 02 is limited to 29 days.

Date in format YYYYMMDD Year between [1900-2099] No leap year check but month 02 is limited to 29 days.

Perfect Date validator from 1900-01-01 to 2013-12-31, all with leap years and perfect dates.

Validates DateTime of format YYYY-MM-DD hh:mm:ss including Leap Year

Validate and capture dateTime parts, includes validation for leap years, range 1000-2999. Fixed bug

Validate and Capture (in 1000-2999 range) Leap-Year Correct

Validate Gregorian calendar dates that contain 24-hour times. This will also correctly match the Feb 29 date when it falls on a valid leap year. Leap years occur every 4 years, with one exception: when a year is evenly divisible by 100 but not evenly divisible by 400, the year will not be a leap year. Thus years 2100, 2200, and 2300 are not leap years but years 2000, 2400, and 2800 are.