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

/
/
mgx

Test String

Code Generator

Generated Code

const regex = /^ # begin \s*# some empty spaces (?: \+? # + symbol \d{1,2} # country code \s* (?(?=\)) # if followed by parens | # then dash not allowed -? # else optional dash ) )? #prefix like +380 \s* (?: (?P<leftparen>\()? # optional left paren \s* 0\d\d \s* (?(leftparen)\)|) # right paren if and only if left paren )? # operator code, starting with 0, optinally in parentheses (?(?<=\)) # if preceded by parens \s*| # then dash not allowed \s*-?\s* # else optional dash ) (?: \d | (?<= \d ) (?(sep) (?P=sep)| (?P<sep>[\-\/\ ]) ) (?= \d ) ){5,13} \s*# some empty spaces $ # end #\d\d\d (?P<separator>-?) \d\d (?P=separator) \d\d $/mg; // Alternative syntax using RegExp constructor // const regex = new RegExp('^ # begin \\s*# some empty spaces (?: \\+? # + symbol \\d{1,2} # country code \\s* (?(?=\\)) # if followed by parens | # then dash not allowed -? # else optional dash ) )? #prefix like +380 \\s* (?: (?P<leftparen>\\()? # optional left paren \\s* 0\\d\\d \\s* (?(leftparen)\\)|) # right paren if and only if left paren )? # operator code, starting with 0, optinally in parentheses (?(?<=\\)) # if preceded by parens \\s*| # then dash not allowed \\s*-?\\s* # else optional dash ) (?: \\d | (?<= \\d ) (?(sep) (?P=sep)| (?P<sep>[\\-\\\/\\ ]) ) (?= \\d ) ){5,13} \\s*# some empty spaces $ # end #\\d\\d\\d (?P<separator>-?) \\d\\d (?P=separator) \\d\\d $', 'mg') const str = `SHOULD MATCH: 5344654 5344654 534-46-54 17189280121 +19173010176 (095)789-58-75 (095) 789-58-75 0957895875 917 229 2897 +38 (095) 5344654 53-475-34 555-1-333 1-333-484 888-333-4 (094)999-22-44 38-095-432-43-34 095-432-43-34 123456 53465 SHOULD NOT MATCH: 1 -1234 38-(095)-432-43-34 534-46/54 (094)999/22-44 1234--567 (345)5345654 (0955344654 095)5345654 `; // 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