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

const regex = /^[ \t]*[A-Z]+(?: [A-Z0-9-]+)+[ \t]+[0-9]{7}[ \t]+.*(?:\r?\n(?![ \t]*$).*)*/gm; // Alternative syntax using RegExp constructor // const regex = new RegExp('^[ \\t]*[A-Z]+(?: [A-Z0-9-]+)+[ \\t]+[0-9]{7}[ \\t]+.*(?:\\r?\\n(?![ \\t]*$).*)*', 'gm') const str = ` DATE: 02 July 2019 -------------------------------------------------------------------------------------------- WELL NAME LICENCE NUMBER MINERAL RIGHTS GROUND ELEVATION UNIQUE IDENTIFIER SURFACE CO-ORDINATES BOARD FIELD CENTRE PROJECTED DEPTH LAHEE CLASSIFICATION FIELD TERMINATING ZONE DRILLING OPERATION WELL PURPOSE WELL TYPE SUBSTANCE LICENSEE SURFACE LOCATION -------------------------------------------------------------------------------------------- MEG K7N HARDY 4-7-77-5 0483923 ALBERTA CROWN 571.7M 106/04-07-077-05W4/02 S 572.4M W 278.3M BONNYVILLE 1600.0M DEV (NC) HARDY MCMURRAY FM HORIZONTAL RESUMPTIONPRODUCTION (SCHEME) CRUDE BITUMEN MEG ENERGY CORP. 09-07-077-05W4 SPL 11-24 HZ MARTEN 14-25-76-6 0494994 ALBERTA CROWN 705.3M 100/14-25-076-06W5/00 S 566.0M E 800.6M ST. ALBERT 2700.0M OUT (C) MARTEN CLEARWATER FM HORIZONTAL NEW PRODUCTION CRUDE OIL SPUR PETROLEUM LTD. 11-24-076-06W5 SPL 10-24 HZ MARTEN 5-23-76-6 0494995 ALBERTA CROWN 705.5M 100/05-23-076-06W5/00 S 566.3M W 800.1M ST. ALBERT 2700.0M OUT (C) MARTEN CLEARWATER FM HORIZONTAL NEW PRODUCTION CRUDE OIL SPUR PETROLEUM LTD. 10-24-076-06W5 SURGE ENERGY HZ103 VALHALLA 6-7-75-8 0494996 ALBERTA CROWN 770.8M 103/06-07-075-08W6/00 S 372.0M E 324.5M GRANDE PRAIRIE 3350.0M DEV (NC) VALHALLA DOIG FM HORIZONTAL NEW PRODUCTION CRUDE OIL SURGE ENERGY INC. 13-06-075-08W6 CNRL ET AL HZ KARR 4-16-66-3 0494997 ALBERTA CROWN 770.7M 100/04-16-066-03W6/00 N 623.4M E 127.5M GRANDE PRAIRIE 5295.0M DEV (NC) KARR DUNVEGAN FM HORIZONTAL NEW PRODUCTION CRUDE OIL CANADIAN NATURAL RESOURCES LIMITED 05-14-066-03W6 `; // Reset `lastIndex` if this regex is defined globally // regex.lastIndex = 0; let m; while ((m = regex.exec(str)) !== null) { // This is necessary to avoid infinite loops with zero-width matches if (m.index === regex.lastIndex) { regex.lastIndex++; } // The result can be accessed through the `m`-variable. m.forEach((match, groupIndex) => { console.log(`Found match, group ${groupIndex}: ${match}`); }); }

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 JavaScript, please visit: https://developer.mozilla.org/en/docs/Web/JavaScript/Guide/Regular_Expressions