Regular Expressions 101

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  • All Tokens
  • Common Tokens
  • General Tokens
  • Anchors
  • Meta Sequences
  • Quantifiers
  • Group Constructs
  • Character Classes
  • Flags/Modifiers
  • Substitution
  • A single character of: a, b or c
    [abc]
  • A character except: a, b or c
    [^abc]
  • A character in the range: a-z
    [a-z]
  • A character not in the range: a-z
    [^a-z]
  • A character in the range: a-z or A-Z
    [a-zA-Z]
  • Any single character
    .
  • Alternate - match either a or b
    a|b
  • Any whitespace character
    \s
  • Any non-whitespace character
    \S
  • Any digit
    \d
  • Any non-digit
    \D
  • Any word character
    \w
  • Any non-word character
    \W
  • Non-capturing group
    (?:...)
  • Capturing group
    (...)
  • Zero or one of a
    a?
  • Zero or more of a
    a*
  • One or more of a
    a+
  • Exactly 3 of a
    a{3}
  • 3 or more of a
    a{3,}
  • Between 3 and 6 of a
    a{3,6}
  • Start of string
    ^
  • End of string
    $
  • A word boundary
    \b
  • Non-word boundary
    \B

Regular Expression
No Match

/
/
gi

Test String

Code Generator

Language

Generated Code

# coding=utf8 # the above tag defines encoding for this document and is for Python 2.x compatibility import re regex = r"(msie\s[5-9])" test_str = ("#IE 11\n" "Mozilla/5.0 (Windows NT 6.1; WOW64; Trident/7.0; AS; rv:11.0) like Gecko\n" "Mozilla/5.0 (compatible, MSIE 11, Windows NT 6.3; Trident/7.0; rv:11.0) like Gecko\n" "Mozilla/5.0 (compatible; MSIE 10.6; Windows NT 6.1; Trident/5.0; InfoPath.2; SLCC1; .NET CLR 3.0.4506.2152; .NET CLR 3.5.30729; .NET CLR 2.0.50727) 3gpp-gba UNTRUSTED/1.0\n\n" "#IE 10\n" "Mozilla/5.0 (compatible; MSIE 10.0; Windows NT 7.0; InfoPath.3; .NET CLR 3.1.40767; Trident/6.0; en-IN)\n" "Mozilla/5.0 (compatible; MSIE 10.0; Windows NT 6.1; WOW64; Trident/6.0)\n" "Mozilla/5.0 (compatible; MSIE 10.0; Windows NT 6.1; Trident/6.0)\n" "Mozilla/5.0 (compatible; MSIE 10.0; Windows NT 6.1; Trident/5.0)\n" "Mozilla/5.0 (compatible; MSIE 10.0; Windows NT 6.1; Trident/4.0; InfoPath.2; SV1; .NET CLR 2.0.50727; WOW64)\n" "Mozilla/5.0 (compatible; MSIE 10.0; Macintosh; Intel Mac OS X 10_7_3; Trident/6.0)\n" "Mozilla/4.0 (compatible; MSIE 10.0; Windows NT 6.1; Trident/5.0)\n" "Mozilla/1.22 (compatible; MSIE 10.0; Windows 3.1)\n\n" "#IE 9\n" "Mozilla/5.0 (Windows; U; MSIE 9.0; WIndows NT 9.0; en-US))\n" "Mozilla/5.0 (Windows; U; MSIE 9.0; Windows NT 9.0; en-US)\n" "Mozilla/5.0 (compatible; MSIE 9.0; Windows NT 7.1; Trident/5.0)\n" "Mozilla/5.0 (compatible; MSIE 9.0; Windows NT 6.1; WOW64; Trident/5.0; SLCC2; Media Center PC 6.0; InfoPath.3; MS-RTC LM 8; Zune 4.7)\n" "Mozilla/5.0 (compatible; MSIE 9.0; Windows NT 6.1; WOW64; Trident/5.0; SLCC2; Media Center PC 6.0; InfoPath.3; MS-RTC LM 8; Zune 4.7\n" "Mozilla/5.0 (compatible; MSIE 9.0; Windows NT 6.1; WOW64; Trident/5.0; SLCC2; .NET CLR 2.0.50727; .NET CLR 3.5.30729; .NET CLR 3.0.30729; Media Center PC 6.0; Zune 4.0; InfoPath.3; MS-RTC LM 8; .NET4.0C; .NET4.0E)\n" "Mozilla/5.0 (compatible; MSIE 9.0; Windows NT 6.1; WOW64; Trident/5.0; chromeframe/12.0.742.112)\n" "Mozilla/5.0 (compatible; MSIE 9.0; Windows NT 6.1; WOW64; Trident/5.0; .NET CLR 3.5.30729; .NET CLR 3.0.30729; .NET CLR 2.0.50727; Media Center PC 6.0)\n" "Mozilla/5.0 (compatible; MSIE 9.0; Windows NT 6.1; Win64; x64; Trident/5.0; .NET CLR 3.5.30729; .NET CLR 3.0.30729; .NET CLR 2.0.50727; Media Center PC 6.0)\n" "Mozilla/5.0 (compatible; MSIE 9.0; Windows NT 6.1; Win64; x64; Trident/5.0; .NET CLR 2.0.50727; SLCC2; .NET CLR 3.5.30729; .NET CLR 3.0.30729; Media Center PC 6.0; Zune 4.0; Tablet PC 2.0; InfoPath.3; .NET4.0C; .NET4.0E)\n" "Mozilla/5.0 (compatible; MSIE 9.0; Windows NT 6.1; Win64; x64; Trident/5.0\n" "Mozilla/5.0 (compatible; MSIE 9.0; Windows NT 6.1; Trident/5.0; yie8)\n" "Mozilla/5.0 (compatible; MSIE 9.0; Windows NT 6.1; Trident/5.0; SLCC2; .NET CLR 2.0.50727; .NET CLR 3.5.30729; .NET CLR 3.0.30729; Media Center PC 6.0; InfoPath.2; .NET CLR 1.1.4322; .NET4.0C; Tablet PC 2.0)\n" "Mozilla/5.0 (compatible; MSIE 9.0; Windows NT 6.1; Trident/5.0; FunWebProducts)\n" "Mozilla/5.0 (compatible; MSIE 9.0; Windows NT 6.1; Trident/5.0; chromeframe/13.0.782.215)\n" "Mozilla/5.0 (compatible; MSIE 9.0; Windows NT 6.1; Trident/5.0; chromeframe/11.0.696.57)\n" "Mozilla/5.0 (compatible; MSIE 9.0; Windows NT 6.1; Trident/5.0) chromeframe/10.0.648.205\n" "Mozilla/5.0 (compatible; MSIE 9.0; Windows NT 6.1; Trident/4.0; GTB7.4; InfoPath.1; SV1; .NET CLR 2.8.52393; WOW64; en-US)\n" "Mozilla/5.0 (compatible; MSIE 9.0; Windows NT 6.0; Trident/5.0; chromeframe/11.0.696.57)\n" "Mozilla/5.0 (compatible; MSIE 9.0; Windows NT 6.0; Trident/4.0; GTB7.4; InfoPath.3; SV1; .NET CLR 3.1.76908; WOW64; en-US)\n\n" "#IE 8\n" "Mozilla/5.0 (compatible; MSIE 8.0; Windows NT 6.1; Trident/4.0; GTB7.4; InfoPath.2; SV1; .NET CLR 3.3.69573; WOW64; en-US)\n" "Mozilla/5.0 (compatible; MSIE 8.0; Windows NT 6.0; Trident/4.0; WOW64; Trident/4.0; SLCC2; .NET CLR 2.0.50727; .NET CLR 3.5.30729; .NET CLR 3.0.30729; .NET CLR 1.0.3705; .NET CLR 1.1.4322)\n" "Mozilla/5.0 (compatible; MSIE 8.0; Windows NT 6.0; Trident/4.0; InfoPath.1; SV1; .NET CLR 3.8.36217; WOW64; en-US)\n" "Mozilla/5.0 (compatible; MSIE 8.0; Windows NT 6.0; Trident/4.0; .NET CLR 2.7.58687; SLCC2; Media Center PC 5.0; Zune 3.4; Tablet PC 3.6; InfoPath.3)\n" "Mozilla/5.0 (compatible; MSIE 8.0; Windows NT 5.2; Trident/4.0; Media Center PC 4.0; SLCC1; .NET CLR 3.0.04320)\n" "Mozilla/5.0 (compatible; MSIE 8.0; Windows NT 5.1; Trident/4.0; SLCC1; .NET CLR 3.0.4506.2152; .NET CLR 3.5.30729; .NET CLR 1.1.4322)\n" "Mozilla/5.0 (compatible; MSIE 8.0; Windows NT 5.1; Trident/4.0; InfoPath.2; SLCC1; .NET CLR 3.0.4506.2152; .NET CLR 3.5.30729; .NET CLR 2.0.50727)\n" "Mozilla/5.0 (compatible; MSIE 8.0; Windows NT 5.1; Trident/4.0; .NET CLR 1.1.4322; .NET CLR 2.0.50727)\n" "Mozilla/5.0 (compatible; MSIE 8.0; Windows NT 5.1; SLCC1; .NET CLR 1.1.4322)\n" "Mozilla/5.0 (compatible; MSIE 8.0; Windows NT 5.0; Trident/4.0; InfoPath.1; SV1; .NET CLR 3.0.4506.2152; .NET CLR 3.5.30729; .NET CLR 3.0.04506.30)\n" "Mozilla/5.0 (compatible; MSIE 7.0; Windows NT 5.0; Trident/4.0; FBSMTWB; .NET CLR 2.0.34861; .NET CLR 3.0.3746.3218; .NET CLR 3.5.33652; msn OptimizedIE8;ENUS)\n" "Mozilla/4.0 (compatible; MSIE 8.0; Windows NT 6.2; Trident/4.0; SLCC2; .NET CLR 2.0.50727; .NET CLR 3.5.30729; .NET CLR 3.0.30729; Media Center PC 6.0)\n" "Mozilla/4.0 (compatible; MSIE 8.0; Windows NT 6.1; WOW64; Trident/4.0; SLCC2; Media Center PC 6.0; InfoPath.2; MS-RTC LM 8)\n" "Mozilla/4.0 (compatible; MSIE 8.0; Windows NT 6.1; WOW64; Trident/4.0; SLCC2; Media Center PC 6.0; InfoPath.2; MS-RTC LM 8\n" "Mozilla/4.0 (compatible; MSIE 8.0; Windows NT 6.1; WOW64; Trident/4.0; SLCC2; .NET CLR 2.0.50727; Media Center PC 6.0; .NET CLR 3.5.30729; .NET CLR 3.0.30729; .NET4.0C)\n" "Mozilla/4.0 (compatible; MSIE 8.0; Windows NT 6.1; WOW64; Trident/4.0; SLCC2; .NET CLR 2.0.50727; InfoPath.3; .NET4.0C; .NET4.0E; .NET CLR 3.5.30729; .NET CLR 3.0.30729; MS-RTC LM 8)\n" "Mozilla/4.0 (compatible; MSIE 8.0; Windows NT 6.1; WOW64; Trident/4.0; SLCC2; .NET CLR 2.0.50727; InfoPath.2)\n" "Mozilla/4.0 (compatible; MSIE 8.0; Windows NT 6.1; WOW64; Trident/4.0; SLCC2; .NET CLR 2.0.50727; .NET CLR 3.5.30729; .NET CLR 3.0.30729; Media Center PC 6.0; Zune 3.0)\n" "Mozilla/4.0 (compatible; MSIE 8.0; Windows NT 6.1; WOW64; Trident/4.0; SLCC2; .NET CLR 2.0.50727; .NET CLR 3.5.30729; .NET CLR 3.0.30729; Media Center PC 6.0; msn OptimizedIE8;ZHCN)\n" "Mozilla/4.0 (compatible; MSIE 8.0; Windows NT 6.1; WOW64; Trident/4.0; SLCC2; .NET CLR 2.0.50727; .NET CLR 3.5.30729; .NET CLR 3.0.30729; Media Center PC 6.0; MS-RTC LM 8; InfoPath.3; .NET4.0C; .NET4.0E) chromeframe/8.0.552.224\n\n" "#IE 7\n" "Mozilla/4.0(compatible; MSIE 7.0b; Windows NT 6.0)\n" "Mozilla/4.0 (compatible; MSIE 7.0b; Windows NT 6.0)\n" "Mozilla/4.0 (compatible; MSIE 7.0b; Windows NT 5.2; .NET CLR 1.1.4322; .NET CLR 2.0.50727; InfoPath.2; .NET CLR 3.0.04506.30)\n" "Mozilla/4.0 (compatible; MSIE 7.0b; Windows NT 5.1; Media Center PC 3.0; .NET CLR 1.0.3705; .NET CLR 1.1.4322; .NET CLR 2.0.50727; InfoPath.1)\n" "Mozilla/4.0 (compatible; MSIE 7.0b; Windows NT 5.1; FDM; .NET CLR 1.1.4322)\n" "Mozilla/4.0 (compatible; MSIE 7.0b; Windows NT 5.1; .NET CLR 1.1.4322; InfoPath.1; .NET CLR 2.0.50727)\n" "Mozilla/4.0 (compatible; MSIE 7.0b; Windows NT 5.1; .NET CLR 1.1.4322; InfoPath.1)\n" "Mozilla/4.0 (compatible; MSIE 7.0b; Windows NT 5.1; .NET CLR 1.1.4322; Alexa Toolbar; .NET CLR 2.0.50727)\n" "Mozilla/4.0 (compatible; MSIE 7.0b; Windows NT 5.1; .NET CLR 1.1.4322; Alexa Toolbar)\n" "Mozilla/4.0 (compatible; MSIE 7.0b; Windows NT 5.1; .NET CLR 1.1.4322; .NET CLR 2.0.50727)\n" "Mozilla/4.0 (compatible; MSIE 7.0b; Windows NT 5.1; .NET CLR 1.1.4322; .NET CLR 2.0.40607)\n" "Mozilla/4.0 (compatible; MSIE 7.0b; Windows NT 5.1; .NET CLR 1.1.4322)\n" "Mozilla/4.0 (compatible; MSIE 7.0b; Windows NT 5.1; .NET CLR 1.0.3705; Media Center PC 3.1; Alexa Toolbar; .NET CLR 1.1.4322; .NET CLR 2.0.50727)\n" "Mozilla/5.0 (Windows; U; MSIE 7.0; Windows NT 6.0; en-US)\n" "Mozilla/5.0 (Windows; U; MSIE 7.0; Windows NT 6.0; el-GR)\n" "Mozilla/5.0 (Windows; U; MSIE 7.0; Windows NT 5.2)\n" "Mozilla/5.0 (MSIE 7.0; Macintosh; U; SunOS; X11; gu; SV1; InfoPath.2; .NET CLR 3.0.04506.30; .NET CLR 3.0.04506.648)\n" "Mozilla/5.0 (compatible; MSIE 7.0; Windows NT 6.0; WOW64; SLCC1; .NET CLR 2.0.50727; Media Center PC 5.0; c .NET CLR 3.0.04506; .NET CLR 3.5.30707; InfoPath.1; el-GR)\n" "Mozilla/5.0 (compatible; MSIE 7.0; Windows NT 6.0; SLCC1; .NET CLR 2.0.50727; Media Center PC 5.0; c .NET CLR 3.0.04506; .NET CLR 3.5.30707; InfoPath.1; el-GR)\n" "Mozilla/5.0 (compatible; MSIE 7.0; Windows NT 6.0; fr-FR)\n" "Mozilla/5.0 (compatible; MSIE 7.0; Windows NT 6.0; en-US)\n" "Mozilla/5.0 (compatible; MSIE 7.0; Windows NT 5.2; WOW64; .NET CLR 2.0.50727)\n" "Mozilla/5.0 (compatible; MSIE 7.0; Windows 98; SpamBlockerUtility 6.3.91; SpamBlockerUtility 6.2.91; .NET CLR 4.1.89;GB)\n" "Mozilla/4.79 [en] (compatible; MSIE 7.0; Windows NT 5.0; .NET CLR 2.0.50727; InfoPath.2; .NET CLR 1.1.4322; .NET CLR 3.0.04506.30; .NET CLR 3.0.04506.648)\n" "Mozilla/4.0 (Windows; MSIE 7.0; Windows NT 5.1; SV1; .NET CLR 2.0.50727)\n" "Mozilla/4.0 (Mozilla/4.0; MSIE 7.0; Windows NT 5.1; FDM; SV1; .NET CLR 3.0.04506.30)\n" "Mozilla/4.0 (Mozilla/4.0; MSIE 7.0; Windows NT 5.1; FDM; SV1)\n" "Mozilla/4.0 (compatible;MSIE 7.0;Windows NT 6.0)\n" "Mozilla/4.0 (compatible; MSIE 7.0; Windows NT 6.2; Win64; x64; Trident/6.0; .NET4.0E; .NET4.0C)\n" "Mozilla/4.0 (compatible; MSIE 7.0; Windows NT 6.1; WOW64; SLCC2; .NET CLR 2.0.50727; InfoPath.3; .NET4.0C; .NET4.0E; .NET CLR 3.5.30729; .NET CLR 3.0.30729; MS-RTC LM 8)\n" "Mozilla/4.0 (compatible; MSIE 7.0; Windows NT 6.1; WOW64; SLCC2; .NET CLR 2.0.50727; .NET CLR 3.5.30729; .NET CLR 3.0.30729; Media Center PC 6.0; MS-RTC LM 8; .NET4.0C; .NET4.0E; InfoPath.3)\n" "Mozilla/4.0 (compatible; MSIE 7.0; Windows NT 6.1; Trident/6.0; SLCC2; .NET CLR 2.0.50727; .NET CLR 3.5.30729; .NET CLR 3.0.30729; .NET4.0C; .NET4.0E)\n" "Mozilla/4.0 (compatible; MSIE 7.0; Windows NT 6.1; SLCC2; .NET CLR 2.0.50727; .NET CLR 3.5.30729; .NET CLR 3.0.30729; Media Center PC 6.0; .NET4.0C; chromeframe/12.0.742.100)\n\n" "#IE 6\n" "Mozilla/4.0 (compatible; MSIE 6.1; Windows XP; .NET CLR 1.1.4322; .NET CLR 2.0.50727)\n" "Mozilla/4.0 (compatible; MSIE 6.1; Windows XP)\n" "Mozilla/4.0 (compatible; MSIE 6.01; Windows NT 6.0)\n" "Mozilla/4.0 (compatible; MSIE 6.0b; Windows NT 5.1; DigExt)\n" "Mozilla/4.0 (compatible; MSIE 6.0b; Windows NT 5.1)\n" "Mozilla/4.0 (compatible; MSIE 6.0b; Windows NT 5.0; YComp 5.0.2.6)\n" "Mozilla/4.0 (compatible; MSIE 6.0b; Windows NT 5.0; YComp 5.0.0.0) (Compatible; ; ; Trident/4.0)\n" "Mozilla/4.0 (compatible; MSIE 6.0b; Windows NT 5.0; YComp 5.0.0.0)\n" "Mozilla/4.0 (compatible; MSIE 6.0b; Windows NT 5.0; .NET CLR 1.1.4322)\n" "Mozilla/4.0 (compatible; MSIE 6.0b; Windows NT 5.0)\n" "Mozilla/4.0 (compatible; MSIE 6.0b; Windows NT 4.0; .NET CLR 1.0.2914)\n" "Mozilla/4.0 (compatible; MSIE 6.0b; Windows NT 4.0)\n" "Mozilla/4.0 (compatible; MSIE 6.0b; Windows 98; YComp 5.0.0.0)\n" "Mozilla/4.0 (compatible; MSIE 6.0b; Windows 98; Win 9x 4.90)\n" "Mozilla/4.0 (compatible; MSIE 6.0b; Windows 98)\n" "Mozilla/4.0 (compatible; MSIE 6.0b; Windows NT 5.1)\n" "Mozilla/4.0 (compatible; MSIE 6.0b; Windows NT 5.0; .NET CLR 1.0.3705)\n" "Mozilla/4.0 (compatible; MSIE 6.0b; Windows NT 4.0)\n" "Mozilla/5.0 (Windows; U; MSIE 6.0; Windows NT 5.1; SV1; .NET CLR 2.0.50727)\n" "Mozilla/5.0 (compatible; MSIE 6.0; Windows NT 5.1; SV1; .NET CLR 2.0.50727)\n" "Mozilla/5.0 (compatible; MSIE 6.0; Windows NT 5.1; SV1; .NET CLR 1.1.4325)\n" "Mozilla/5.0 (compatible; MSIE 6.0; Windows NT 5.1)\n" "Mozilla/45.0 (compatible; MSIE 6.0; Windows NT 5.1)\n" "Mozilla/4.08 (compatible; MSIE 6.0; Windows NT 5.1)\n" "Mozilla/4.01 (compatible; MSIE 6.0; Windows NT 5.1)\n" "Mozilla/4.0 (X11; MSIE 6.0; i686; .NET CLR 1.1.4322; .NET CLR 2.0.50727; FDM)\n" "Mozilla/4.0 (Windows; MSIE 6.0; Windows NT 6.0)\n" "Mozilla/4.0 (Windows; MSIE 6.0; Windows NT 5.2)\n" "Mozilla/4.0 (Windows; MSIE 6.0; Windows NT 5.0)\n" "Mozilla/4.0 (Windows; MSIE 6.0; Windows NT 5.1; SV1; .NET CLR 2.0.50727)\n" "Mozilla/4.0 (MSIE 6.0; Windows NT 5.1)\n" "Mozilla/4.0 (MSIE 6.0; Windows NT 5.0)\n" "Mozilla/4.0 (compatible;MSIE 6.0;Windows 98;Q312461)\n" "Mozilla/4.0 (Compatible; Windows NT 5.1; MSIE 6.0) (compatible; MSIE 6.0; Windows NT 5.1; .NET CLR 1.1.4322; .NET CLR 2.0.50727)\n" "Mozilla/4.0 (compatible; U; MSIE 6.0; Windows NT 5.1) (Compatible; ; ; Trident/4.0; WOW64; Trident/4.0; SLCC2; .NET CLR 2.0.50727; .NET CLR 3.5.30729; .NET CLR 3.0.30729; .NET CLR 1.0.3705; .NET CLR 1.1.4322)\n" "Mozilla/4.0 (compatible; U; MSIE 6.0; Windows NT 5.1)\n" "Mozilla/4.0 (compatible; MSIE 8.0; Windows NT 6.1; Trident/4.0; Mozilla/4.0 (compatible; MSIE 6.0; Windows NT 5.1; SV1) ; SLCC2; .NET CLR 2.0.50727; .NET CLR 3.5.30729; .NET CLR 3.0.30729; Media Center PC 6.0; .NET4.0C; InfoPath.3; Tablet PC 2.0)\n" "Mozilla/4.0 (compatible; MSIE 8.0; Windows NT 6.1; Trident/4.0; GTB6.5; QQDownload 534; Mozilla/4.0 (compatible; MSIE 6.0; Windows NT 5.1; SV1) ; SLCC2; .NET CLR 2.0.50727; Media Center PC 6.0; .NET CLR 3.5.30729; .NET CLR 3.0.30729)\n") matches = re.finditer(regex, test_str, re.IGNORECASE) for matchNum, match in enumerate(matches, start=1): print ("Match {matchNum} was found at {start}-{end}: {match}".format(matchNum = matchNum, start = match.start(), end = match.end(), match = match.group())) for groupNum in range(0, len(match.groups())): groupNum = groupNum + 1 print ("Group {groupNum} found at {start}-{end}: {group}".format(groupNum = groupNum, start = match.start(groupNum), end = match.end(groupNum), group = match.group(groupNum))) # Note: for Python 2.7 compatibility, use ur"" to prefix the regex and u"" to prefix the test string and substitution.

Please keep in mind that these code samples are automatically generated and are not guaranteed to work. If you find any syntax errors, feel free to submit a bug report. For a full regex reference for Python, please visit: https://docs.python.org/3/library/re.html