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"^(?P<operating_fluid>M)(?P<sep_1>-)(?P<unit_type>SR)(?P<unit_size>\d{1,2})(?P<mounting_type>K)(?P<unit_design>E|D)(?P<cracking_pressure>\d{1,3})(?P<sep_2>-)(?P<unit_series>1X)(?P<sep_3>/)(?P<seal_material>V|)(?P<additional_details>(.|[0-9])*)$\n"), flags=re.MULTILINE) test_str = ("M-SR6KD05-1X/\n" "M-SR8KD05-1X/\n" "M-SR10KD05-1X/\n" "M-SR20KD05-1X/\n" "M-SR25KD05-1X/\n" "M-SR30KD05-1X/\n" "M-SR6KD15-1X/\n" "M-SR8KD15-1X/\n" "M-SR10KD15-1X/\n" "M-SR20KD15-1X/\n" "M-SR25KD15-1X/\n" "M-SR30KD15-1X/\n" "M-SR6KD30-1X/\n" "M-SR8KD30-1X/\n" "M-SR10KD30-1X/\n" "M-SR20KD30-1X/\n" "M-SR25KD30-1X/\n" "M-SR30KD30-1X/\n" "M-SR6KD02-1X/\n" "M-SR8KD02-1X/\n" "M-SR20KD02-1X/\n" "M-SR25KD02-1X/\n" "M-SR30KD02-1X/\n" "M-SR10KD50-1X/\n" "M-SR20KD50-1X/\n" "M-SR25KD50-1X/\n" "M-SR30KD50-1X/\n" "M-SR10KD02-1X/\n" "M-SR6KD50-1X/\n" "M-SR10KD05-1X/B12\n" "M-SR8KD05-1X/B06\n" "M-SR30KD00-1X/\n" "M-SR20KE05-1X/VSO13\n" "M-SR20KE05-1X/\n" "M-SR10KE05-1X/\n" "M-SR25KE05-1X/\n" "M-SR30KE05-1X/\n" "M-SR15KE05-1X/\n" "M-SR30KE02-1X/\n" "M-SR20KE02-1X/\n" "M-SR10KE02-1X/\n" "M-SR30KE30-1X/\n" "M-SR15KE30-1X/\n" "M-SR8KE05-1X/\n" "M-SR10KE50-1X/V\n" "M-SR25KE30-1X/\n" "M-SR20KE30-1X/\n" "M-SR10KE15-1X/\n" "M-SR15KE15-1X/\n" "M-SR20KE15-1X/\n" "M-SR10KE30-1X/\n" "M-SR8KE15-1X/\n" "M-SR20KE50-1X/\n" "M-SR8KE30-1X/\n" "M-SR25KE15-1X/\n" "M-SR10KE05-1X/V\n" "M-SR30KE15-1X/\n" "M-SR20KE15-1X/V\n" "M-SR15KE50-1X/\n" "M-SR15KE02-1X/\n" "M-SR30KE50-1X/\n" "M-SR15KE05-1X/V\n" "M-SR20KE05-1X/V\n" "M-SR30KE50-1X/V\n" "M-SR30KE05-1X/V\n" "M-SR20KE00-1X/\n" "M-SR25KE50-1X/\n" "M-SR30KE00-1X/\n" "M-SR8KE50-1X/\n" "M-SR10KE00-1X/\n" "M-SR25KE50-1X/V\n" "M-SR30KE30-1X/V\n" "M-SR30KE02-1X/V\n" "M-SR8KE02-1X/\n" "M-SR25KE05-1X/V\n" "M-SR8KE05-1X/V\n" "M-SR25KE02-1X/\n" "M-SR15KE00-1X/\n" "M-SR8KE02-1X/V\n" "M-SR15KE50-1X/V\n" "M-SR8KE00-1X/\n" "M-SR10KE50-1X/\n" "M-SR25KE00-1X/\n" "M-SR8KE05-1X/SO1\n" "M-SR8KE00-1X/V\n" "M-SR10KE02-1X/V\n" "M-SR20KE02-1X/V\n" "M-SR30KE15-1X/V\n" "M-SR10KE30-1X/V\n" "M-SR15KE30-1X/V\n" "M-SR20KE00-1X/V\n" "M-SR25KE30-1X/V\n" "M-SR15KE15-1X/V\n" "M-SR15KE02-1X/V\n" "M-SR20KE05-1X/MT\n" "M-SR8KE15-1X/V\n" "M-SR25KE50-1X/SO6\n" "M-SR25KE00-1X/V\n" "M-SR15KE00-1X/V\n" "M-SR20KE30-1X/V\n" "M-SR20KE05-1X/SO1\n" "M-SR10KE15-1X/V\n" "M-SR8KE05-1X/VSO1\n" "M-SR8KE50-1X/V\n" "M-SR20KE50-1X/V\n" "M-SR8KE05-1X/SO11\n" "M-SR15KE05-1X/MT\n" "M-SR10KE05-1X/SO1\n" "M-SR8KE05-1X/MT\n" "M-SR15KE05-1X/SO1\n" "M-SR8KE30-1X/V\n" "M-SR10KE00-1X/V\n" "M-SR25KE15-1X/V\n" "M-SR30KE00-1X/V\n" "M-SR15KE05-1X/SO13\n" "M-SR8KE05-1X/SO14\n" "M-SR10KE02-1X/SO1\n" "M-SR20KE15-1X/MT\n" "M-SR15KE05-1X/SO18\n" "M-SR25KE05-1X/SO11\n" "M-SR8KE02-1X/SO11\n" "M-SR8KE02-1X/SO1\n" "M-SR10KE50-1X/MT\n" "M-SR30KE30-1X/MT\n" "M-SR30KE05-1X/MT\n" "M-SR25KE02-1X/V\n" "M-SR25KE05-1X/MT\n" "M-SR15KE30-1X/MT\n" "M-SR30KE05-1X/SO11\n" "M-SR20KE02-1X/MT\n" "M-SR10KE02-1X/SO14\n" "M-SR10KE05-1X/MT\n" "M-SR15KE50-1X/SO11\n" "M-SR8KE02-1X/VSO11\n" "M-SR8KE02-1X/VSO1\n" "M-SR30KE50-1X/SO11\n" "M-SR25KE50-1X/SO11\n" "M-SR20KE05-1X/SO11\n" "M-SR10KE05-1X/VSO11\n" "M-SR8KE02-1X/MT\n" "M-SR8KE50-1X/MT\n" "M-SR25KE15-1X/MT\n" "M-SR15KE50-1X/MT\n" "M-SR20KE30-1X/MT\n" "M-SR25KE30-1X/MT\n" "M-SR30KE30-1X/SO14\n" "M-SR30KE120-1X/SO28\n" "M-SR30KE60-1X/MT\n" "M-SR10KE01-1X/\n" "M-SR15KE01-1X/\n" "M-SR8KE01-1X/\n" "M-SR30KE01-1X/\n" "M-SR25KE01-1X/\n" "M-SR20KE01-1X/\n" "M-SR30KE120-1X/\n") 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