Regular Expressions 101

Save & Share

Flavor

  • PCRE2 (PHP >=7.3)
  • PCRE (PHP <7.3)
  • ECMAScript (JavaScript)
  • Python
  • Golang
  • Java 8
  • .NET 7.0 (C#)
  • Rust
  • Regex Flavor Guide

Function

  • Match
  • Substitution
  • List
  • Unit Tests

Tools

Sponsors
There are currently no sponsors. Become a sponsor today!
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 single character of: a, b, c or d
    [[ab][cd]]
  • 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]
  • Character class intersection
    [\w&&[^\d]]
  • 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 = new RegExp('(\\+?[\\d]{1,3}([-]{0,2}|[\\s]+)?)?\\(?(\\d{3})\\)?([-]{0,2}|[\\s])?(\\d{3})([-]{0,2}|[\\s])?(\\d{4})(\\s?(([E|e]xt[:|.|]?)|x|X)(\\s?\\d+))?', 'gm') const str = `1645162589000 1-718-444-1122 718-444-1122 (718)-444-1122 17184441122 7184441122 718.444.1122 1718.444.1122 1-123-456-7890 1 123-456-7890 1 (123) 456-7890 1 123 456 7890 1.123.456.7890 +91 (123) 456-7890 18005551234 1 800 555 1234 +1 800 555-1234 +86 800 555 1234 1-800-555-1234 1 (800) 555-1234 (800)555-1234 (800) 555-1234 (800)5551234 800-555-1234 800.555.1234 18001234567 1 800 123 4567 1-800-123-4567 +18001234567 +1 800 123 4567 +1 (800) 123 4567 1(800)1234567 +1800 1234567 1.8001234567 1.800.123.4567 +1 (800) 123-4567 18001234567 1 800 123 4567 +1 800 123-4567 +86 800 123 4567 1-800-123-4567 1 (800) 123-4567 (800)123-4567 (800) 123-4567 (800)1234567 800-123-4567 800.123.4567 1231231231 123-1231231 123123-1231 123-123 1231 123 123-1231 123-123-1231 (123)123-1231 (123)123 1231 (123) 123-1231 (123) 123 1231 +99 1234567890 +991234567890 (555) 444-6789 555-444-6789 555.444.6789 555 444 6789 18005551234 1 800 555 1234 +1 800 555-1234 +86 800 555 1234 1-800-555-1234 1.800.555.1234 +1.800.555.1234 1 (800) 555-1234 (800)555-1234 (800) 555-1234 (800)5551234 800-555-1234 800.555.1234 (003) 555-1212 (103) 555-1212 (911) 555-1212 18005551234 1 800 555 1234 +86 800-555-1234 1 (800) 555-1234 1234567890 Ext: 1123123 1234567890Ext: 1123123 1234567890 Ext:1123123`; // 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