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 = /^(\w+)\s+(\w+)(\(\d*\))?.*$/gm; // Alternative syntax using RegExp constructor // const regex = new RegExp('^(\\w+)\\s+(\\w+)(\\(\\d*\\))?.*$', 'gm') const str = `userId bigint(20) NO PRI auto_increment createDate datetime YES modifiedDate datetime YES password_ varchar(75) YES passwordEncrypted tinyint(4) YES passwordModifiedDate datetime YES sAMAccountName varchar(255) YES MUL screenName varchar(75) YES UNI screenNameModifiedDate datetime YES emailAddress varchar(75) YES MUL firstName varchar(75) YES lastName varchar() YES lastLoginDate datetime YES active_ tinyint(4) YES MUL phone varchar(25) YES token varchar(75) YES tokenValidUntil datetime YES deletedAt datetime YES deletedByUserId bigint(20) YES eightByEightId varchar(100) YES fitPushToken varchar(255) YES -- query 2: WORKORDER_NO varchar(32) NO PRI WORKORDER_RES_ID varchar(18) NO PRI ATTR_ID varchar(60) NO PRI ATTR_NAME varchar(40) NO ATTR_DISP_NAME varchar(256) YES ATTR_VAL varchar(4000) YES CONTROL_TYPE char(1) YES DATA_SOURCE text YES CONTROL_FLAG char(1) YES ATTR_FLAG char(1) NO DATA_TYPE char(1) YES DATA_LEN int(4) YES PRECISION int(2) YES SCALE int(2) YES IS_NULL char(1) YES INIT_VALUE varchar(80) YES STATE char(1) NO A CREATE_USER decimal(9,0) YES CREATE_DATE datetime YES MODIFY_USER decimal(9,0) YES MODIFY_DATE datetime YES `; // 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