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 = /me/gm; // Alternative syntax using RegExp constructor // const regex = new RegExp('me', 'gm') const str = `https://lingojam.com/edit/02db819202047a0e482ab768cd7baec9 ###name, Name of your translator...: IRC Server Now Understands Voice ###subtitle, Subtitle (optional): The Only Way ###language1, Language1 name...: Antonio Rodriguez Jr. Command To Anything ###language2, Language2 name...: Antonio Rodriguez Jr. Is Now Heard, Seen, Felt, Sense, And Vice Verca ###description, Description...: import java.util.Scanner Scanner stdin = new Scanner(System.in) public class Command { public static void main(String[] args) { System.out.println("Command:"); } ###email, Admin email (optional)...: wonderfulyanderful@gmail.com ###phrases1, Language1...: ###phrases2, Language2...: ###words1, Language1...: ###words2, Language2...: ###intraword1, Language1...: ###intraword2, Language2...: ###prefixes1, Language1...: ###prefixes2, Language2...: ###suffixes1, Language1...: ###suffixes2, Language2...: ###regex1, Replace this...: ###regex2, with this...: ###rev_regex1, Replace this...: ###rev_regex2, with this...: ###ordering1, Language1...: ###ordering2, Language2...: ###defaulttext, One random default text string per line...: ###disable-reverse, : on ###custom-script, Define your functions here...: ###title-extra, e.g. '(and reverse translation)': ###background-image-source, http://example.com/my_image.png: ###title-font-name, Name of custom font...: ###title-font-size, Size of title (default=5.5)...: ###language1-font, Language1 font...: ###language2-font, Language2 font...: ###language1-font-size, Language1 font size (default=24)...: ###language2-font-size, Language2 font size (default=24)...: `; // 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