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

r"
"
gmx

Test String

Code Generator

Generated Code

const regex = new RegExp('^([MF]\\/\\d{2})\\/ (?#Gender/Age, required.) ( (?#Height, required.) (?:\\d{1}[\\\\'\\’]? (?#Optional \\\\'\\’ unit markings.) (?: (?#Groups starting with ?: are non-capturing.) (?: [02-9]|1[01]? )(?:[\\"”]|\\\\'\\\\')? (?#Optional "\\\\'\\\\' unit markings.) )? )| \\d{1,3}cm| [12]m(?:\\d{1,2}(?:cm)?)? (?#Optional cm unit marking.) )\\ ? (?#Weight before to after, required. ?P<weight> is a named capturing group, associated with match sub-pattern ?P=weight. It forces the user to be consistent, either using only lbs, or only kg for the entire match, also used in Lifting Stats section.) \\[(\\d{2,3}\\ ?(?P<weight>lbs|kg)\\ to\\ \\d{2,3}\\ ?(?P=weight))\\]\\ ? (?# Optional space before lbs|kg. *Changed to require space before and after "to".) \\( (?#Time Period, required) ( (?:\\d{1,2}\\ ?years?)| (?#Optional space before years, optional s in years.) (?: (?:[2-9]|1[01]?)\\ ?(?:month|week)s? (?#Optional space before months|weeks, optional s at end.) )| (?:\\d{1,2}\\ ?years?[;,]?\\ ? (?#Optional space before years, optional s in years. Optional space after.) (?:[02-9]|1[01]?)\\ ?months?)| (?#Optional space before monthss, optional s in months.) ) \\)\\ ? (?:\\ ?\\+\\ ?\\( (?#Lifting Stats, optional. Optional space before/after + .) ((?:[DSBO]:\\ ?(?:\\d{2,3})\\ ?(?P=weight)(?:[;,]\\ ?)?){1,4}) (?# Optional space after [DSBO]: . Optional space before lbs|kg. Optional space after ;, delimiter. Changed from 4 repeated statements to one recursive group.) \\)(?<=[sg]\\)))? (?# ?<= is a Positive Lookbehind. It requires the ; or , delimiter between stats, but prevents the delimiter after the last stat.) (\\ .*)? (?#Comments, optional. *Changed: Required space before comments section.) $|^\\[Meta\\].*', 'gm') const str = `M/24/5'10" [175lbs to 150lbs] (1 year)`; // 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