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]
  • Character class intersection
    [\w&&[^\d]]
  • 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"Support Escalations*[\s\S]*?Level IV.*", flags=re.MULTILINE) test_str = ("<td valign=\"top\"><br>\n" "<br>\n" "John Doe<br>\n" "Example, Inc. <br>\n" "<br>\n" "Office: 212.777.9999 x295<br>\n" "jdoe@example.com| transbeam.com <br>\n" "<br>\n" "Support Escalations<br>\n" "Level I: NOC Technician - support@example.com | O: 989.571.1000<br>\n" "Level II: Manager, Network &amp; Eng Operations, William Tell - wchen@example.com | O: 212.777.9999 x123 | M: 989.265.9876<br>\n" "Level III: Vice President, Operations, Blaise Pascal - blaisep@example.com | O: 212.777.9999 x234 | M: 343.301.2822 <br>\n" "Level IV: Chief Operating Officer: BF Skinner - bskinner@example.com | O: 212.777.9999 x345 | M: 343.337.7775<br>\n" "<br>\n" " <br>\n" "<br>\n" "From: Example Tech Support <br>\n" "Sent: Monday, August 7, 2017 3:27 PM<br>\n" "To: Example Tech Support <support@example.com>; 'nocdata@sample.com' <nocdata@sample.com><br>\n" "Subject: RE: 81434 | WIN - Reparian Riverfront - EoC 10MB - Partial Impact<br>\n" "<br>\n" "Sample Support,<br>\n" "<br>\n" "Please be advised all loops have been repaired for this customer and they are currently up at their Full Bandiwdth.<br>\n" "As this is stable, We will close this ticket out.<br>\n" "<br>\n" "Please let us know if you have any questions.<br>\n" "<br>\n" "Thank you,<br>\n" "<br>\n" "John Doe<br>\n" "Example, Inc. <br>\n" "<br>\n" "Office: 212.777.9999 x295<br>\n" "jdoe@example.com| transbeam.com <br>\n" "<br>\n" "Support Escalations<br>\n" "Level I: NOC Technician - support@example.com | O: 989.571.1000<br>\n" "Level II: Manager, Network &amp; Eng Operations, William Tell - wchen@example.com | O: 212.777.9999 x123 | M: 989.265.9876<br>\n" "Level III: Vice President, Operations, Blaise Pascal - blaisep@example.com | O: 212.777.9999 x234 | M: 343.301.2822 <br>\n" "Level IV: Chief Operating Officer: BF Skinner - bskinner@example.com | O: 212.777.9999 x345 | M: 343.337.7775<br>\n" "<br>\n" " <br>\n" "<br>\n" "From: Example Tech Support <br>\n" "Sent: Thursday, August 3, 2017 9:24 AM<br>\n" "To: Example Tech Support <support@example.com>; 'nocdata@sample.com' <nocdata@sample.com><br>\n" "Subject: RE: 81434 | WIN - Reparian Riverfront - EoC 10MB - Partial Impact<br>\n" "<br>\n" "Correction. The commit on the new ticket (loop 4) is 08/16. Apologies for the error.<br>\n" "<br>\n" "-------------------------------------<br>\n" "Judy Garland<br>\n" "NOC Technician<br>\n" "<br>\n" "From: Example Tech Support <br>\n" "Sent: Thursday, August 03, 2017 9:22 AM<br>\n" "To: 'nocdata@sample.com'<br>\n" "Cc: Example Tech Support<br>\n" "Subject: 81434 | WIN - Reparian Riverfront - EoC 10MB - Partial Impact<br>\n" "<br>\n" "Hello,<br>\n" "<br>\n" "Update regarding results of ILEC dispatch to prem this date. ILEC technician repaired the loop that was down (loop 3), but another loop (loop 4) developed a problem while he was there and is now bouncing. Loop 4 has been removed from the efm-group to prevent it from affecting the circuit and a ticket opened with the ILEC for its repair (commit 08/14).<br>\n" "<br>\n" "At this time, the 10Mb circuit is up at 9.8Mbps on 3 loops.<br>\n" "<br>\n" "<br>\n" "If you have any further questions, comments or concerns regarding this message, please contact Example NOC support as documented below.<br>\n" "<br>\n" "Thank you,<br>\n" "<br>\n" "-------------------------------------<br>\n" "Judy Garland<br>\n" "NOC Technician<br>\n" "<br>\n" "transbeam.com<br>\n" "<br>\n" "=======================================================================<br>\n" "Support Escalations<br>\n" "Level I: NOC Technician - support@example.com | O: 989.571.1000<br>\n" "Level II: Manager, Network Operations, William Tell - wchen@example.com | O: 212.777.9999 x123 | M: 989.265.9876<br>\n" "Level III: Vice President, Operations, Blaise Pascal - blaisep@example.com | O: 212.777.9999 x234 | M: 343.301.2822 <br>\n" "Level IV: Chief Operating Officer: BF Skinner - bskinner@example.com | O: 212.777.9999 x345 | M: 343.337.7775<br>\n" "<br>\n\n" " </td>") 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