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

/
/
gm

Test String

Code Generator

Language

Generated Code

const regex = /(,+(.+[A-Z]{2} [0-9-]+)(,.*)(http.*[-._A-Za-z]+.[a-z]+),([-0-9]+),([- 0-9a-z]+))|(,+(.+[A-Z]{2} [0-9-]+))/gm; // Alternative syntax using RegExp constructor // const regex = new RegExp('(,+(.+[A-Z]{2} [0-9-]+)(,.*)(http.*[-._A-Za-z]+.[a-z]+),([-0-9]+),([- 0-9a-z]+))|(,+(.+[A-Z]{2} [0-9-]+))', 'gm') const str = `,P.O. Box 11000 Montgomery, AL 36191-0001 334-288-3900,,vvv ,,15520 Rockfield Blvd. Ste. C Irvine, CA 92618-2792,...Whether you are looking for a list broker, list manager, database marketing or data processing profe*ssional, 's experienced...,http://www.carneydirect.com,949-581-5100,949-581-4564 fax,., ,115 Sansome Street San Francisco, CA 94104-4508,...We are a "Results Agency" based in San Francisco that is dedicated to producing top performing creative and strategy for...,http://www.creativelift.net,415-248-3174,415-398-0144 fax,., ,,2051 Dogwood Street Suite 220 Louisville, CO 80027,...The premier database marketing solutions provider and behavioral targeting firm for multi-channel marketers and advertisers. You can create, build and...,http://www.i-behavior.com,303-228-5000,303-... ,198 Scribner Ave. Norwalk, CT 06854-1324,...I am an email marketing and direct marketing consultant. I help companies build, execute and analyze their customer acquisition...,http://www.reggiebrady.com,203-838-8138,.,,,,,, ,RMI Direct Marketing,,44 Old Ridgebury Road, Plaza One Danbury, CT 06810-5129,...RMI is a premier customer acquisition, data and insert management firm. We specialize in market and competitor analysis, acquisition plans,...,http://www.rmidirect.com,203-798-0448,203-778-6130 fax,.,`; // 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