OWASP Validation Regex Repository

Note

These Regexs are examples and not built for a particular Regex engine. However, the PCRE syntax is mainly used. In particular, this means that character classes do not contain meta characters which need to be escaped, except the - and ] character, where it is assumed that a - needs not to be escaped only when it is the last character in a character class. The character class supports shortcut notations for other character classes like \s or \w which should not be used as they depend on the LOCALE environment setting in most systems.

Please carefully test the regex in your regex engine.

<?xml version="1.0"?> 

  <regex>
  	<name>url</name>
  	<pattern><![CDATA[^((((https?|ftps?|gopher|telnet|nntp)://)|(mailto:|news:))(%[0-9A-Fa-f]{2}|[-()_.!~*';/?:@&=+$,A-Za-z0-9])+)([).!';/?:,][[:blank:]])?$]]></pattern>
  	<description>A valid URL per the URL spec.</description>
  </regex>

  <regex>
  	<name>IP</name>
  	<pattern><![CDATA[^(25[0-5]|2[0-4][0-9]|[01]?[0-9][0-9]?)\.(25[0-5]|2[0-4][0-9]|[01]?[0-9][0-9]?)\.(25[0-5]|2[0-4][0-9]|[01]?[0-9][0-9]?)\.(25[0-5]|2[0-4][0-9]|[01]?[0-9][0-9]?)$]]></pattern>
  	<description>A valid IP Address</description>
  </regex>

  <regex>
  	<name>e-mail</name>
  	<pattern><![CDATA[^[a-zA-Z0-9_+&*-]+(?:\.[a-zA-Z0-9_+&*-]+)*@(?:[a-zA-Z0-9-]+\.)+[a-zA-Z]{2,7}$]]></pattern>
  	<description>A valid e-mail address</description>
  </regex>

  <regex>
  	<name>safetext</name>
  	<pattern><![CDATA[^[a-zA-Z0-9 .-]+$]]></pattern>
  	<description>Lower and upper case letters and all digits</description>
  </regex>

  <regex>
  	<name>date</name>
  	<pattern><![CDATA[^(?:(?:(?:0?[13578]|1[02])(\/|-|\.)31)\1|(?:(?:0?[1,3-9]|1[0-2])(\/|-|\.)(?:29|30)\2))(?:(?:1[6-9]|[2-9]\d)?\d{2})$|^(?:0?2(\/|-|\.)29\3(?:(?:(?:1[6-9]|[2-9]\d)?(?:0[48]|[2468][048]|[13579][26])|(?:(?:16|[2468][048]|[3579][26])00))))$|^(?:(?:0?[1-9])|(?:1[0-2]))(\/|-|\.)(?:0?[1-9]|1\d|2[0-8])\4(?:(?:1[6-9]|[2-9]\d)?\d{2})$]]></pattern>
  	<description>Date in US format with support for leap years</description>
  </regex>

  <regex>
  	<name>creditcard</name>
  	<pattern><![CDATA[^((4\d{3})|(5[1-5]\d{2})|(6011)|(7\d{3}))-?\d{4}-?\d{4}-?\d{4}|3[4,7]\d{13}$]]></pattern>
  	<description>A valid credit card number</description>
  </regex>

  <regex>
  	<name>password</name>
  	<pattern><![CDATA[^(?=.*\d)(?=.*[a-z])(?=.*[A-Z]).{4,8}$]]></pattern>
  	<description>4 to 8 character password requiring numbers and both lowercase and uppercase letters</description>
  </regex>

  <regex>
  	<name>complexpassword</name>
  	<pattern><![CDATA[^(?:(?=.*\d)(?=.*[A-Z])(?=.*[a-z])|(?=.*\d)(?=.*[^A-Za-z0-9])(?=.*[a-z])|(?=.*[^A-Za-z0-9])(?=.*[A-Z])(?=.*[a-z])|(?=.*\d)(?=.*[A-Z])(?=.*[^A-Za-z0-9]))(?!.*(.)\1{2,})[A-Za-z0-9!~<>,;:_=?*+#."&§%°()\|\[\]\-\$\^\@\/]{8,32}$]]></pattern>
  	<description>4 to 32 character password requiring at least 3 out 4 (uppercase and lowercase letters, numbers and special characters) and no more than 2 equal characters in a row</description>
  </regex>

  <regex>
  	<name>English_digitwords</name>
  	<pattern><![CDATA[^(zero|one|two|three|four|five|six|seven|eight|nine)$]]></pattern>
  	<description>The English words representing the digits 0 to 9</description>
  </regex>

  <regex>
  	<name>English_daywords</name>
  	<pattern><![CDATA[^(Mo|Tu|We|Th|Fr|Sa|Su)$]]></pattern>
  	<description>English 2 character abbreviations for the days of the week</description>
  </regex> 

  <regex>
  	<name>English_monthwords</name>
  	<pattern><![CDATA[^(Jan|Feb|Mar|Apr|May|Jun|Jul|Aug|Sep|Oct|Nov|Dec)$]]></pattern>
  	<description>English 3 character abbreviations for the months</description>
  </regex>

  <regex>
  	<name>French_digitwords</name>
  	<pattern><![CDATA[^(z[eé]ro|un|deux|trois|quatre|cinq|six|sept|huit|neuf)$]]></pattern>
  	<description>The French words representing the digits 0 to 9</description>
  </regex>

  <regex>
  	<name>German_digitwords</name>
  	<pattern><![CDATA[^(null|eins|zwei|drei|vier|f(ue|ü)nf|sechs|sieben|acht|neun)$]]></pattern>
  	<description>The German words representing the digits 0 to 9</description>
  </regex>

  <regex>
  	<name>Spanish_digitwords</name>
  	<pattern><![CDATA[^(cero|uno|dos|tres|cuatro|cinco|seis|siete|ocho|nueve)$]]></pattern>
  	<description>The Spanish words representing the digits 0 to 9</description>
  </regex>

  <regex>
  	<name>US_zip</name>
  	<pattern><![CDATA[^\d{5}(-\d{4})?$]]></pattern>
  	<description>US zip code with optional dash-four</description>
  </regex>

  <regex>
  	<name>US_phone</name>
  	<pattern><![CDATA[^\D?(\d{3})\D?\D?(\d{3})\D?(\d{4})$]]></pattern>
  	<description>US phone number with or without dashes</description>
  </regex>

  <regex>
  	<name>US_state</name>
  	<pattern><![CDATA[^(AE|AL|AK|AP|AS|AZ|AR|CA|CO|CT|DE|DC|FM|FL|GA|GU|HI|ID|IL|IN|IA|KS|KY|LA|ME|MH|MD|MA|MI|MN|MS|MO|MP|MT|NE|NV|NH|NJ|NM|NY|NC|ND|OH|OK|OR|PW|PA|PR|RI|SC|SD|TN|TX|UT|VT|VI|VA|WA|WV|WI|WY)$]]></pattern>
  	<description>2 letter U.S. state abbreviations</description>
  </regex>

  <regex>
  	<name>US_ssn</name>
  	<pattern><![CDATA[^\d{3}-\d{2}-\d{4}$]]></pattern>
  	<description>9 digit U.S. social security number with dashes</description>
  </regex>

  <!-- Some additional examples that have not been vetted
  
       // HTML HEX CODE   ^#?([a-f]|[A-F]|[0-9]){3}(([a-f]|[A-F]|[0-9]){3})?$
       // FLOATING POINT   ^[-+]?[0-9]+[.]?[0-9]*([eE][-+]?[0-9]+)?$
       // PERSON NAME   ^[a-zA-Z]+(([',. -][a-zA-Z ])?[a-zA-Z]*)*$
       // MAC ADDRESS  ^([0-9a-fA-F][0-9a-fA-F]:){5}([0-9a-fA-F][0-9a-fA-F])$
       // GUID    ^[A-Z0-9]{8}-[A-Z0-9]{4}-[A-Z0-9]{4}-[A-Z0-9]{4}-[A-Z0-9]{12}$
       // IP ADDRESS  ^\b((25[0-5]|2[0-4]\d|[01]\d\d|\d?\d)\.){3}(25[0-5]|2[0-4]\d|[01]\d\d|\d?\d)\b$
       // IP ADDRESS (^\b(?:(?:25[0-5]|2[0-4][0-9]|[01]?[0-9][0-9]?)\.){3}(?:25[0-5]|2[0-4][0-9]|[01]?[0-9][0-9]?)\b$
       // REASONABLE DOMAIN NAME   ^([a-zA-Z0-9]([a-zA-Z0-9\-]{0,61}[a-zA-Z0-9])?\.)+[a-zA-Z]{2,6}$
       // RFC 1918 NON ROUTABLE IP   ^(((25[0-5]|2[0-4][0-9]|19[0-1]|19[3-9]|18[0-9]|17[0-1]|17[3-9]|1[0-6][0-9]|1[1-9]|[2-9][0-9]|[0-9])\.(25[0-5]|2[0-4][0-9]|1[0-9][0-9]|[1-9][0-9]|[0-9]))|(192\.(25[0-5]|2[0-4][0-9]|16[0-7]|169|1[0-5][0-9]|1[7-9][0-9]|[1-9][0-9]|[0-9]))|(172\.(25[0-5]|2[0-4][0-9]|1[0-9][0-9]|1[0-5]|3[2-9]|[4-9][0-9]|[0-9])))\.(25[0-5]|2[0-4][0-9]|1[0-9][0-9]|[1-9][0-9]|[0-9])\.(25[0-5]|2[0-4][0-9]|1[0-9][0-9]|[1-9][0-9]|[0-9])$
       // VALID WINDOWS FILENAME  ^(?!^(PRN|AUX|CLOCK\$|NUL|CON|COM\d|LPT\d|\..*)(\..+)?$)[^\x00-\x1f\\?*:\";|/]+$
       //
       //
       // Warning, per http://en.wikipedia.org/wiki/ReDoS the Java Classname RegEx below is vulnerable to RegExDos
       // Java Classname  ^(([a-z])+.)+[A-Z]([a-z])+$
       // The correct RegEx for java classnames is the following one, and not vulnerable:
       // Java Classname  ^(([a-z])+\.)+[A-Z]([a-zA-Z])+$
       //
       //  ANY PLATFORM FILENAME   ^(([a-zA-Z]:|\\)\\)?(((\.)|(\.\.)|([^\\/:*?"|<>. ](([^\\/:*?"|<>. ])|([^\\/:*?"|<>]*[^\\/:*?"|<>. ]))?))\\)*[^\\/:*?"|<>. ](([^\\/:*?"|<>. ])|([^\\/:*?"|<>]*[^\\/:*?"|<>. ]))?$
  -->

Other Regex References

Regex Library Site

http://regexlib.com/: A site that has a HUGE library of regular expressions and other regex resources

Regex Tutorial Site

http://www.regular-expressions.info/: A site with lots of tutorials on writing Regexs and numerous examples

Regex Construction Tool

http://www.ultrapico.com/Expresso.htm: A free regex construction tool

Regex Explanation Tool

http://rick.measham.id.au/paste/explain.pl?regex=.*: Explains in English what the supplied regex means