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

r"
"
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"^(.+ESTABLISHED[\s\S]+?={3}.+?)$" test_str = ("Security Associations (2 up, 0 connecting):\n" " IPSec-IKEv2[2]: ESTABLISHED 10 seconds ago, 5.79.70.34[a.teletom.ru]...91.77.160.189[192.168.1.64]\n" " IPSec-IKEv2[2]: Remote EAP identity: mac\n" " IPSec-IKEv2[2]: IKEv2 SPIs: 8e03bee2f90a7b0f_i 2b840459b2a53517_r*, rekeying disabled\n" " IPSec-IKEv2[2]: IKE proposal: AES_CBC_256/HMAC_SHA2_256_128/PRF_HMAC_SHA2_256/MODP_2048\n" " IPSec-IKEv2{2}: INSTALLED, TUNNEL, reqid 2, ESP in UDP SPIs: ca7323ca_i 0dd681eb_o\n" " IPSec-IKEv2{2}: AES_CBC_128/HMAC_SHA1_96, 63234 bytes_i (390 pkts, 0s ago), 113714 bytes_o (345 pkts, 0s ago), rekeying disabled\n" " IPSec-IKEv2{2}: 0.0.0.0/0 === 10.101.0.2/32\n" " IPSec-IKEv2[1]: ESTABLISHED 8 minutes ago, 5.79.70.34[a.teletom.ru]...91.77.160.189[hon]\n" " IPSec-IKEv2[1]: IKEv2 SPIs: 0fa1c950bdb21ac0_i 0bcd0f3b2bea4cea_r*, rekeying disabled\n" " IPSec-IKEv2[1]: IKE proposal: AES_CBC_128/HMAC_SHA2_256_128/PRF_HMAC_SHA2_256/ECP_256\n" " IPSec-IKEv2{1}: INSTALLED, TUNNEL, reqid 1, ESP in UDP SPIs: cb680131_i 69774a81_o\n" " IPSec-IKEv2{1}: AES_GCM_16_128, 86593 bytes_i (454 pkts, 11s ago), 249805 bytes_o (510 pkts, 11s ago), rekeying disabled\n" " IPSec-IKEv2{1}: 0.0.0.0/0 === 10.101.0.1/32") 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