Regular Expressions 101

Save & Share

  • Regex Version: ver. 4
  • 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

/
/
g

Test String

Code Generator

Language

Generated Code

// include the latest version of the regex crate in your Cargo.toml extern crate regex; use regex::Regex; fn main() { let regex = Regex::new(r"http://www\.myurl\.com/\?action=joingiveaway&amp;id=([0-9]+)").unwrap(); let string = " <DIV> <H2><A style=\"COLOR: black\" href=\"http://www.myurl.com/?action=viewgiveaways&amp;id=287\">New car Giveaway</A></H2></DIV> <DIV style=\"MARGIN-TOP: 6px\">The Winner of this giveaway will win a new car!</DIV> <DIV class=box_round style=\"BORDER-TOP: red 1px solid; BORDER-RIGHT: red 1px solid; BORDER-BOTTOM: red 1px solid; PADDING-BOTTOM: 8px; PADDING-TOP: 8px; PADDING-LEFT: 8px; BORDER-LEFT: red 1px solid; MARGIN-TOP: 10px; PADDING-RIGHT: 8px\"> <DIV><B>Special Requirement : </B></DIV> <DIV style=\"MARGIN-TOP: 2px\">You need to have earned atleast <B style=\"COLOR: blue\">1000 Coins </B>in total to enter this Giveaway </DIV> <DIV style=\"COLOR: green; MARGIN-TOP: 2px\">Your total coin earnings is 21707 </DIV></DIV> <DIV style=\"MARGIN-TOP: 6px\"><B>Entry Fee : 20 Coins</B></DIV> <DIV style=\"MARGIN: 6px\"><A class=cssbutton style=\"COLOR: white\" href=\"http://www.myurl.com/?action=joingiveaway&amp;id=287\">Enter Giveaway</A><BR><SMALL>You have 0 entries</SMALL></DIV></DIV> <DIV style=\"FLOAT: right\"> <DIV>Group : Everyone</DIV> <DIV>Multiple Entries : No</DIV> <DIV>Total Entries : <A href=\"http://www.myurl.com/?action=viewentries&amp;giveawayid=287\">4</A></DIV> <DIV>Max Entries : 100</DIV> <DIV>Start Date : Jan 23 2013</DIV> <DIV><A href=\"http://www.myurl.com/index.php?action=faq#coins\" target=_blank>How To Earn Coins?</A></DIV></DIV> <DIV style=\"CLEAR: both\"></DIV></DIV></DIV></DIV> <DIV class=index-left style=\"FLOAT: right; PADDING-TOP: 15px; PADDING-RIGHT: 23px\"> <DIV class=left-section> "; // result will be an iterator over tuples containing the start and end indices for each match in the string let result = regex.captures_iter(string); for mat in result { println!("{:?}", mat); } }

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 Rust, please visit: https://docs.rs/regex/latest/regex/