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

~
~
gixJ

Test String

Code Generator

Language

Generated Code

const regex = new RegExp('(*UTF16) x (?<! \\w x ) [\\d._ –-]* (*SKIP) (*F) | order (?<! \\w order ) [\\W_]* (?:number)? [\\W_]* [\\d._ –-]* (*SKIP) (*F) | (?<res> [1234578] (?:[._ –-]{0,3}+\\d){2} (?: 0{2} [\\d._ –-]* (*SKIP) (*F) )? (?:[._ –-]{0,3}+\\d){2} ) (?: 0{4} [\\d._ –-]* (*SKIP) (*F) )? (?:[._ –-]{0,3}+\\d){4} | (?<res> 0 (?: 0{2} [\\d._ –-]* (*SKIP) (*F) )? (?: [._ –-]{0,3}+ \\d ){2} (?: 0{2} [\\d._ –-]* (*SKIP) (*F) )? (?: [._ –-]{0,3}+ \\d ){2} ) (?: 0{4} [\\d._ –-]* (*SKIP) (*F) )? (?: [._ –-]{0,3}+ \\d ){4} | (?<res> 6 (?: 6{2} [\\d._ –-]* (*SKIP) (*F) )? (?: [._ –-]{0,3}+ \\d ){2} (?: 0{2} [\\d._ –-]* (*SKIP) (*F) )? (?: [._ –-]{0,3}+ \\d ){2} ) (?: 0{4} [\\d._ –-]* (*SKIP) (*F) )? (?: [._ –-]{0,3}+ \\d ){4} | 9 [\\d._ –-]* (*SKIP) (*F)', 'gi') const str = `//won't match if it is preceded with 'X' or 'x' x123456789 X123456789 x123-456-789 X123-456-789 123-456-789 ordernumber 123-456-789 order number123-456789 order number----123-456789 order number 123456789 ordernumber-x123456787 ordernumber-123456787 ORDERNUMBER-123456789 ordernumber - 123456789 ordernumber #123456789 ordernumber *%&%*123456789 ordernumber !@#\$%^&123456789 order.number 123456789 order_number 123456789 order._.number 123456789 order...number#123456789 order-.-.-.-.123456789 order 123456789 order..123456789 order#123456789 order_#123456789 order._.#123456789 order___123456789 order#number 123456789 order......number 123456789 order.number.123456789 social security number 123-456-789 ordernumber !@#\$%^&x123456789 123456789 #@%#\$%#\$123456789#\$%#\$^\$# 123-456789 123456789 123456789 123 45 6789 123-45-6789 123-45-6789 123 – 45 – 6789 123.45.6789 123_45_6789 123 456 789 123-456-789 123 – 456 – 789 123.456.789 123_456_789 1234 56 789 1234-56-789 1234 – 56 – 789 1234.56.789 1234_56_789 12 345 6789 12-345-6789 12 – 345 – 6789 12.345.6789 12_345_6789 The number should not be matched at all for the following rules. If the number beginning with the number “9” 912345678 912000000 If the number “666” in positions 1 – 3. 666000000 666450000 666129876 If the number “000” in positions 1 – 3. 000000000 000450000 000120000 If the number “00” in positions 4 – 5. 123006789 876001234 765003456 if the number “0000” in positions 6 – 9 123450000 123000000 876000000 x123456789 X123456789 x123-456-789 X123-456-789 `; // 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