Regular Expressions 101

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An explanation of your regex will be automatically generated as you type.
Detailed match information will be displayed here automatically.
  • 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

/
/
gm

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"(((iPhone([\d\W]+)|iPhone|iPad)(;|\s\d+;|\s\w+;|\s\d+\w+;)?(\s+)?(U;)?)(\s+)?(CPU|iOS)([^\);]+)?)" test_str = ("RubyBrowser/46.3.26 (iPhone; iOS 15.0.2; Scale/2.00)\n" "bazaart/7.4.3 (iPhone; iOS 15.0.2; Scale/2.00)\n" "Mozilla/5.0 (iPhone; CPU iPhone OS 13_5_1 like Mac OS X) AppleWebKit/605.1.15 (KHTML, like Gecko) Mobile/15E148 LightSpeed [FBAN/MessengerLiteForiOS;FBAV/294.0.0.60.128;FBBV/262406393;FBDV/iPhone11,8;FBMD/iPhone;FBSN/iOS;FBSV/13.5.1;FBSS/2;FBCR/;FBID/phone;FBLC/en;FBOP/0]\n" "Mozilla/5.0 (iPhone; CPU iPhone OS 14_7_1 like Mac OS X) AppleWebKit/605.1.15 (KHTML, like Gecko) Mobile/15E148 LightSpeed [FBAN/MessengerLiteForiOS;FBAV/332.0.0.45.117;FBBV/321367341;FBDV/iPhone11,2;FBMD/iPhone;FBSN/iOS;FBSV/14.7.1;FBSS/3;FBCR/;FBID/phone;FBLC/en;FBOP/0]\n" " 120572 Mozilla/5.0 (iPhone1 03; CPU iPhone OS 11_0_1 like Mac OS X) AppleWebKit/604.3.5 (KHTML, like Gecko) Version/11.0 MQQBrowser/8.2.1 Mobile/15B87 Safari/604.1 MttCustomUA/2 QBWebViewType/1 WKType/1\n" " 120584 OneDriveiOSApp/12.19.5 (iOS/14.4; en_CA; Apple/iPhone)\n" " 120613 Mozilla/5.0 (iPhone X; CPU iPhone OS 13_4 like Mac OS X) AppleWebKit/605.1.15 (KHTML, like Gecko) Version/13.1 Mobile/15E148 Safari/604.1\n" " 120690 Instagram 175.0.0.23.117 (iPhone8,1; iOS 14_1; de_DE; de-DE; scale=2.00; 750x1334; 272995447) AppleWebKit/420+\n" " 120696 Instagram 175.0.0.23.117 (iPhone13,1; iOS 14_2_1; it_IT; it-IT; scale=2.88; 1080x2338; 272995447) AppleWebKit/420+\n" " 120697 Instagram 174.0.0.21.119 (iPhone12,3; iOS 13_6; it_IT; it-IT; scale=3.00; 1125x2436; 271836321) AppleWebKit/420+\n" "Mozilla/5.0 (iPad; CPU OS 8_4_1 like Mac OS X) AppleWebKit/600.1.4 (KHTML, like Gecko) Version/8.0 Mobile/12H321 Safari/600.1.4\n" "Mozilla/5.0 (iPad; CPU OS 10_3_3 like Mac OS X) AppleWebKit/600.1.4 (KHTML, like Gecko) GSA/7.0.55539 Mobile/14G60 Safari/600.1.4\n" "Mozilla/5.0 (iPad; CPU OS 10_3_2 like Mac OS X) AppleWebKit/603.2.4 (KHTML, like Gecko) Version/10.0 Mobile/14F8089 Safari/602.1\n" "Mozilla/5.0 (iPad; CPU OS 10_3_3 like Mac OS X) AppleWebKit/603.3.8 (KHTML, like Gecko) Version/10.0 Mobile/14G60 Safari/602.1\n" "Mozilla/5.0 (iPad; CPU OS 9_3_2 like Mac OS X) AppleWebKit/601.1 (KHTML, like Gecko) CriOS/63.0.3239.73 Mobile/13F69 Safari/601.1.46\n" "Mozilla/5.0 (iPad; CPU OS 9_3_2 like Mac OS X) AppleWebKit/601.1.46 (KHTML, like Gecko) Version/9.0 Mobile/13F69 Safari/601.1\n" "Mozilla/5.0 (iPhone; CPU iPhone OS 7_0 like Mac OS X) AppleWebKit/537.51.1 (KHTML, like Gecko) Version/7.0 Mobile/11A465 Safari/9537.53 (compatible; bingbot/2.0; +http://www.bing.com/bingbot.htm)\n" "Mozilla/5.0 (iPhone; CPU iPhone OS 7_0_2 like Mac OS X) AppleWebKit/537.51.1 (KHTML, like Gecko) CriOS/30.0.1599.12 Mobile/11A501 Safari/8536.25 MicroMessenger/6.1.0\n" "Mozilla/5.0 (iPhone; CPU iPhone OS 11_3 like Mac OS X) AppleWebKit/605.1.15 (KHTML, like Gecko) Version/11.0 Mobile/15E148 Safari/604.1\n" "Mozilla/5.0 (iPhone; CPU iPhone OS 10_2_1 like Mac OS X) AppleWebKit/602.4.6 (KHTML, like Gecko) Mobile/14D27 MicroMessenger/6.5.5 NetType/WIFI Language/zh_CN\n") matches = re.finditer(regex, test_str, re.MULTILINE) 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