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

/
/
g

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"(https?:\/\/[-|\w\.|\/]+)" test_str = (" <div class=\"col-sm-8\"><p>TLX is a Flat-Face twist lock coupling for the toughest applications in the construction and demolition segment. This super-duty quick connect coupling is designed to work with the highest surge flows and the toughest pressure impulses. TLX is made from high alloy steels with Zinc-Nickel surface treatment for a long life in the harshest conditions. The Series is available in sizes from ½” to 1 ½” to cover most applications.</p><br /><p>- The couplings and nipples are also available in 4 other sizes: ¾” (Series 607) 1” (Series 707) 1 ¼” (Series 807) and 1 ½ ” (Series 907) https://www.cejn.com/globalassets/documents/brochures/tlx-en.pdf</p></div>\n\n" " <div class=\"col-sm-4\">\n" " <img src=\"/globalassets/product/cejn/series-507/group/series-507-tlx-group-cejn.jpg?w=275\" rel=\"lightbox\" alt=\"Series 507 - &#189;”\" class=\"cboxElement\" />\n" " </div>\n") matches = re.finditer(regex, test_str) 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