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"Hagestein boven.+?(?:<td>Waterhoogte<\/td><td>)(.\d*)") test_str = ">H10</td><td><a target=\"_blank\" href = \"http://www.rws.nl/images/GRAVBVN_tcm174-335817.pdf\">meer</a></td></tr><tr><td><a href='awd.php?mode=html&amp;projecttype=waterstanden&amp;category=1&amp;loc=GREB&amp;net=LMW'>Grebbe</a></td><td>21/04 17:30</td><td>Waterhoogte</td><td>643</td><td>cm NAP</td><td>LMW</td><td>GREB</td><td>H10</td><td></td></tr><tr><td><a href='awd.php?mode=html&amp;projecttype=waterstanden&amp;category=1&amp;loc=GREV&amp;net=LMW'>Grevenbicht</a></td><td>21/04 17:30</td><td>Waterhoogte</td><td>2623</td><td>cm NAP</td><td>LMW</td><td>GREV</td><td>H10</td><td><a target=\"_blank\" href = \"http://www.rws.nl/images/GREVBT_tcm174-335691.pdf\">meer</a></td></tr><tr><td><a href='awd.php?mode=html&amp;projecttype=waterstanden&amp;category=1&amp;loc=GRPO&amp;net=LMW'>Groene Riv Pannerden ben</a></td><td>21/04 17:30</td><td>Waterhoogte</td><td>1143</td><td>cm NAP</td><td>LMW</td><td>GRPO</td><td>H10</td><td></td></tr><tr><td><a href='awd.php?mode=html&amp;projecttype=waterstanden&amp;category=1&amp;loc=GRPB&amp;net=LMW'>Groene Riv Pannerden bov</a></td><td>21/04 17:30</td><td>Waterhoogte</td><td>1153</td><td>cm NAP</td><td>LMW</td><td>GRPB</td><td>H10</td><td></td></tr><tr><td><a href='awd.php?mode=html&amp;projecttype=waterstanden&amp;category=1&amp;loc=HAAN&amp;net=LMW'>Haandrik Kruisbrug</a></td><td>21/04 17:30</td><td>Waterhoogte</td><td>910</td><td>cm NAP</td><td>LMW</td><td>HAAN</td><td>H10</td><td></td></tr><tr><td><a href='awd.php?mode=html&amp;projecttype=waterstanden&amp;category=1&amp;loc=HAGO&amp;net=LMW'>Hagestein beneden</a></td><td>21/04 17:30</td><td>Waterhoogte</td><td>98</td><td>cm NAP</td><td>LMW</td><td>HAGO</td><td>H10</td><td><a target=\"_blank\" href = \"http://www.rws.nl/images/HAGSBNDN_tcm174-335693.pdf\">meer</a></td></tr><tr><td><a href='awd.php?mode=html&amp;projecttype=waterstanden&amp;category=1&amp;loc=HAGB&amp;net=LMW'>Hagestein boven</a></td><td>21/04 17:30</td><td>Waterhoogte</td><td>272</td><td>cm NAP</td><td>LMW</td><td>HAGB</td><td>H10</td><td><a target=\"_blank\" href = \"http://www.rws.nl/images/HAGSBVN_tcm174-335697.pdf\">meer</a></td></tr><tr><td><a href='awd.php?mode=html&amp;projecttype=waterstanden&amp;category=1&amp;loc=HANS&amp;net=LMW'>Hansweert</a></td><td>21/04 17:30</td><td>Waterhoogte</td><td>180</td><td>cm NAP</td><td>LMW</td><td>HANS</td><td>H10</td><td><a target=\"_blank\" href = \"http://www.rws.nl/images/HANSWT_tcm174-335699.pdf\">meer</a></td></tr><tr><td><a href='awd.php?mode=html&amp;projecttype=waterstanden&amp;category=1&amp;loc=HAWIb&amp;net=LMW'>Hansweert wind (b)</a></td><td>21/04 17:30</td><td>Waterhoogte</td><td>179</td><td>cm NAP</td><td>LMW</td><td>HAWIb</td><td>H10</td><td></td></tr><tr><td><a href='awd.php?m" match = regex.search(test_str) if match: print(f"Match 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