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 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

/
/
ig

Test String

Code Generator

Language

Generated Code

const regex = /[NMS]\w+\-\w*BASE\w*\.AD\.DTI/ig; // Alternative syntax using RegExp constructor // const regex = new RegExp('[NMS]\\w+\\-\\w*BASE\\w*\\.AD\\.DTI', 'ig') const str = `MAVM-WLBASE1a.ad.dti. MAVM-WLBASE2a.ad.dti. MAVM-WLBASE3a.ad.dti. MAVM-WLBASE4a.ad.dti. MAVM-WLBASE5a.ad.dti. NJ-BASEQA2015.ad.dti. NJVM-BASEQA2014.ad.dti. NJVM-WLBASE6b.ad.dti. NJVM-WLBASE7a.ad.dti. NY2-BASEQA.ad.dti. NY2-DW5BASEQA01.ad.dti. SHVM-WLBASE1A.ad.dti. NJ-ODEV2015.ad.dti. NJ-ODEV2015b.ad.dti. NJVM-ODEV2014.ad.dti. NY2-ODEV2017.ad.dti. SH-ODEV2017.ad.dti. MOVM-WL12C.ad.dti. NJ-PASWL12c01.ad.dti. NJ-WL12cSVT01.ad.dti. NJVM-WL12CUST1.ad.dti. NJVM-wl12cust2.ad.dti. njvm-wl12cust4.ad.dti. njvm-wl12x64j7a.ad.dti. NY2-WL12asp01.ad.dti. NY2-WL12ASP02.ad.dti. NY2-WL12ASP03.ad.dti. NY2-WL12ASP04.ad.dti. SH-AutoITWL12.ad.dti. SH-PASWL12c02.ad.dti. SHVM-WL12-RE.ad.dti. SHVM-WL12CUST3.ad.dti. ASP-WL1213INT01.asp.ad.dti. ASP-WL12CEXT5.asp.ad.dti. ASPVM-WL12c10.asp.ad.dti. ASPVM-WL12c8.asp.ad.dti. ASPVM-WL12c9.asp.ad.dti. LT-MPROEKT.ad.dti. LT-jpo01.ad.dti LT-jpo01.adXdti`; // 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