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 (24)

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

/
/
gm

Test String

Code Generator

Language

Generated Code

using System; using System.Text.RegularExpressions; public class Example { public static void Main() { string pattern = @"(?<!\d|-|\/|to|\$)(?<!\$(\d)\.)([1-9][0-9]{0,2}(\.\d{0,2})?\s?)(lbs|lb|LBS|LB|KG|kg|G|g|L|l+)(?!\d|\w)"; string input = @"10lb Potato bag Apples Gld Delicious 3lb Grandfer Rocha Pear2.5lbs CHIN.MAND.5LB Batata Veg (10LB) SIG 170LB99 Legging SzB 1ea ARJO CDA1450035 SupBlk 400LB1ea AHC EB205L DRI 10220-1 Bariatric500lb 1 ea TILDA SONA MASOORI 20 LBS OVAL ROASTER 9 - 12 LBS ORGANIC TRIPACK FRUIT 1.2 KG KGF5KT2404 PEPLUM T, PURPLE AIR 1773LB-XL 15-20 KnXL 1ea PLUM BAG 1KG US NEXT XTRA 100G SUDOCREM 60G EGGPLANT GRILLED IN OIL (3KG) CORONATION GRAPE 2L CA MEAT DEAL $11.00 KG LIVE LOBSTER- 2.00-3.00 LB-MSC PC MAGIC GROW 20-20-20 3.55KG KGF7W3409 KGVELCROWB,GREY TZATZIKI 500G 2+1 LEAD MIX"; RegexOptions options = RegexOptions.Multiline; foreach (Match m in Regex.Matches(input, pattern, options)) { Console.WriteLine("'{0}' found at index {1}.", m.Value, m.Index); } } }

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 C#, please visit: https://msdn.microsoft.com/en-us/library/system.text.regularexpressions.regex(v=vs.110).aspx