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
Processing...

Test String

Code Generator

Language

Generated Code

import re regex = re.compile(r"esdfdsdg", flags=re.MULTILINE) test_str = ("[MediaClient.19516, 2022-09-06T08:55:47.011; Info]: (pjproject_interface_impl.cc:171): pjsua_core.c:459 .RX 2702 bytes Response msg 200/INVITE/cseq=7943 (rdata000001EF7B4F91D0) from TLS 203.252.54.20:443: to 192.259.19.37:59160\n" "SIP/2.0 200 OK\n" "Via: SIP/2.0/TLS 192.259.19.37:59160;rport=59160;received=64.37.175.80;branch=z9hG4bKPj5eaadcef35a3486e9414d26c3b329ba7\n" "Call-ID: 219a7090d9464e5988618fa5d9e022dc\n" "From: \"John dale\" <sip:fiber@service.com>;tag=3a931b11390244bc990d45e82b8345ed\n" "To: \"service\" <sips:c016130e-fa4e-454a-b249-4a6f8d6cf276@sip-203-252-54-20.bjn.vc>;tag=MTAuMTA4LjEyLjE4OjQ1ODExOjI-\n" "CSeq: 7943 INVITE\n" "Contact: \"Service\" <sip:c016130e-fa4e-454a-b249-4a6f8d6cf276@sip-203-252-54-20.cji.vc:443;transport=tls>\n" "Allow: PRACK, INVITE, ACK, BYE, CANCEL, UPDATE, SUBSCRIBE, NOTIFY, REFER, INFO, OPTIONS\n" "Supported: 100rel\n" "Content-Type: application/sdp\n" "Content-Length: 2027\n\n" "v=0\n" "o=BlueJeans 0 3871442120 IN IP4 203.252.54.20\n" "s=-\n" "c=IN IP4 203.252.54.20\n" "t=0 0\n" "a=x-bwmgr:delay\n" "a=extmap:1 http://www.webrtc.org/experiments/rtp-hdrext/abs-send-time\n" "m=audio 42613 RTP/SAVP 121 96\n" "a=crypto:1 AEAD_AES_256_GCM \n" "a=rtcp:42613\n" "a=rtpmap:121 DVC-2/8000\n" "a=rtpmap:96 telephone-event/8000\n" "a=fmtp:96 0-15\n" "a=sendrecv\n" "a=ice-ufrag:b510\n" "a=ice-pwd:2224b63a+7b01+4929+9ba6+\n" "a=candidate:H67ff3614 1 UDP 2130706431 103.255.54.20 42613 typ host\n" "a=rtcp-mux\n" "a=remote-candidates:1 203.252.54.20 26047 2 203.252.54.20 26047\n" "m=video 42614 RTP/SAVP 102 122 116 125\n" "b=TIAS:4096000\n" "a=crypto:1 AEAD_AES_256_GCM \n\n" "--end--msg") matches = regex.finditer(test_str) for match_num, match in enumerate(matches, start=1): print(f"Match {match_num} was found at {match.start()}-{match.end()}: {match.group()}") for group_num, group in enumerate(match.groups(), start=1): print(f"Group {group_num} found at {match.start(group_num)}-{match.end(group_num)}: {group}")

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