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"^[ \t]*[A-Z]+(?: [A-Z0-9-]+)+[ \t]+[0-9]{7}[ \t]+.*(?:\r?\n(?![ \t]*$).*)*", flags=re.MULTILINE) test_str = ("\n\n\n\n" " DATE: 02 July 2019 \n\n\n" " -------------------------------------------------------------------------------------------- \n" " WELL NAME LICENCE NUMBER MINERAL RIGHTS GROUND ELEVATION \n" " UNIQUE IDENTIFIER SURFACE CO-ORDINATES BOARD FIELD CENTRE PROJECTED DEPTH \n" " LAHEE CLASSIFICATION FIELD TERMINATING ZONE \n" " DRILLING OPERATION WELL PURPOSE WELL TYPE SUBSTANCE \n" " LICENSEE SURFACE LOCATION \n" " -------------------------------------------------------------------------------------------- \n\n" " MEG K7N HARDY 4-7-77-5 0483923 ALBERTA CROWN 571.7M \n" " 106/04-07-077-05W4/02 S 572.4M W 278.3M BONNYVILLE 1600.0M \n" " DEV (NC) HARDY MCMURRAY FM \n" " HORIZONTAL RESUMPTIONPRODUCTION (SCHEME) CRUDE BITUMEN \n" " MEG ENERGY CORP. 09-07-077-05W4 \n\n" " SPL 11-24 HZ MARTEN 14-25-76-6 0494994 ALBERTA CROWN 705.3M \n" " 100/14-25-076-06W5/00 S 566.0M E 800.6M ST. ALBERT 2700.0M \n" " OUT (C) MARTEN CLEARWATER FM \n" " HORIZONTAL NEW PRODUCTION CRUDE OIL \n" " SPUR PETROLEUM LTD. 11-24-076-06W5 \n\n" " SPL 10-24 HZ MARTEN 5-23-76-6 0494995 ALBERTA CROWN 705.5M \n" " 100/05-23-076-06W5/00 S 566.3M W 800.1M ST. ALBERT 2700.0M \n" " OUT (C) MARTEN CLEARWATER FM \n" " HORIZONTAL NEW PRODUCTION CRUDE OIL \n" " SPUR PETROLEUM LTD. 10-24-076-06W5 \n\n" " SURGE ENERGY HZ103 VALHALLA 6-7-75-8 0494996 ALBERTA CROWN 770.8M \n" " 103/06-07-075-08W6/00 S 372.0M E 324.5M GRANDE PRAIRIE 3350.0M \n" " DEV (NC) VALHALLA DOIG FM \n" " HORIZONTAL NEW PRODUCTION CRUDE OIL \n" " SURGE ENERGY INC. 13-06-075-08W6 \n\n" " CNRL ET AL HZ KARR 4-16-66-3 0494997 ALBERTA CROWN 770.7M \n" " 100/04-16-066-03W6/00 N 623.4M E 127.5M GRANDE PRAIRIE 5295.0M \n" " DEV (NC) KARR DUNVEGAN FM \n" " HORIZONTAL NEW PRODUCTION CRUDE OIL \n" " CANADIAN NATURAL RESOURCES LIMITED 05-14-066-03W6 ") 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