Regular Expressions 101

Save & Share

  • Regex Version: ver. 3
  • Update Regex
    ctrl+⇧+s
  • Save new Regex
    ctrl+s
  • Add to Community Library

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 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

/
/
i

Test String

Code Generator

Language

Generated Code

import Foundation let pattern = #"(?:https?|ftp):\/\/sun2.[^\s\,]+"# let regex = try! NSRegularExpression(pattern: pattern, options: .caseInsensitive) let testString = #"<a aria-label="фотография" onclick="return showPhoto('-100714248_457263531', 'wall-100714248_195733', {"temp":{"x":"https:\/\/sun1.tattelecom-nbc.userapi.com\/AZsv8R78JOlrmsTJ6NR_NZpKj-RbfbWCPWQ8uA\/QnMLGnxpnYk.jpg","y":"https:\/\/sun1.tattelecom-nbc.userapi.com\/vtKcPNt6Wazn_vcPkvLAMX1MOhMz_hfRgYx28g\/cXJNEGEn2Lc.jpg","z":"https:\/\/sun2.tattelecom-nbc.userapi.com\/oZ0evVUqXklp4UGCisHHFRSaNTEfnnJO_A7lTg\/ZqD22JRrSyw.jpg","x_":["https:\/\/sun1.tattelecom-nbc.userapi.com\/AZsv8R78JOlrmsTJ6NR_NZpKj-RbfbWCPWQ8uA\/QnMLGnxpnYk",359,604],"y_":["https:\/\/sun1.tattelecom-nbc.userapi.com\/vtKcPNt6Wazn_vcPkvLAMX1MOhMz_hfRgYx28g\/cXJNEGEn2Lc",480,807],"z_":["https:\/\/sun2.tattelecom-nbc.userapi.com\/oZ0evVUqXklp4UGCisHHFRSaNTEfnnJO_A7lTg\/ZqD22JRrSyw",587,987],"base":""},"queue":1}, event)" style="width: 68px; height: 115px;background-image: url(https://sun2.tattelecom-nbc.userapi.com/aMS3yYlzjZF3H6GPY1T5oDAeIqZD5uQv4WveMw/7ToUPNMTnmo.jpg);" class="page_post_thumb_wrap image_cover page_post_thumb_last_column fl_l page_post_thumb_not_single" data-photo-id="-100714248_457263531"></a>"# let stringRange = NSRange(location: 0, length: testString.utf16.count) if let firstMatch = regex.firstMatch(in: testString, range: stringRange) { let result: [String] = (1 ..< firstMatch.numberOfRanges).map { (testString as NSString).substring(with: firstMatch.range(at: $0)) } print(result) } else { print("No matches were found.") }

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 Swift 5.2, please visit: https://developer.apple.com/documentation/foundation/nsregularexpression