Regular Expressions 101

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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

import java.util.regex.Matcher; import java.util.regex.Pattern; public class Example { public static void main(String[] args) { final String regex = "^<Version>(.*)<\\/Version>$"; final String string = "<Project Sdk=\"Microsoft.NET.Sdk\">\n" + " <PropertyGroup>\n" + " <TargetFramework>netstandard2.0</TargetFramework>\n" + " <NeutralLanguage>en-US</NeutralLanguage>\n" + " <Authors>Alex Volchetsky</Authors>\n" + " <Company />\n" + " <Product />\n" + " <Description>SDK for Yandex Alice skills development</Description>\n" + " <PackageProjectUrl>https://alexvolchetsky.github.io/yandex.alice.sdk</PackageProjectUrl>\n" + " <RepositoryUrl>https://github.com/alexvolchetsky/yandex.alice.sdk</RepositoryUrl>\n" + " <RepositoryType>git</RepositoryType>\n" + " <PackageTags>yandex alice skill dialogs models</PackageTags>\n" + " <PackageIcon>icon.png</PackageIcon>\n" + " <Version>1.0.4</Version>\n" + " <PackageLicenseFile>LICENSE.md</PackageLicenseFile>\n" + " <PackageReleaseNotes>Add intents integration</PackageReleaseNotes>\n" + " </PropertyGroup>\n\n" + " <ItemGroup>\n" + " <PackageReference Include=\"Microsoft.CodeAnalysis.FxCopAnalyzers\" Version=\"2.9.8\">\n" + " <PrivateAssets>all</PrivateAssets>\n" + " <IncludeAssets>runtime; build; native; contentfiles; analyzers; buildtransitive</IncludeAssets>\n" + " </PackageReference>\n" + " <PackageReference Include=\"Microsoft.Extensions.Options\" Version=\"3.1.5\" />\n" + " <PackageReference Include=\"System.Text.Json\" Version=\"4.7.1\" />\n" + " </ItemGroup>\n\n" + " <ItemGroup>\n" + " <Compile Update=\"Resources\\Yandex.Alice.Sdk.Resources.Designer.cs\">\n" + " <DesignTime>True</DesignTime>\n" + " <AutoGen>True</AutoGen>\n" + " <DependentUpon>Yandex.Alice.Sdk.Resources.resx</DependentUpon>\n" + " </Compile>\n" + " </ItemGroup>\n\n" + " <ItemGroup>\n" + " <EmbeddedResource Update=\"Resources\\Yandex.Alice.Sdk.Resources.resx\">\n" + " <Generator>ResXFileCodeGenerator</Generator>\n" + " <LastGenOutput>Yandex.Alice.Sdk.Resources.Designer.cs</LastGenOutput>\n" + " </EmbeddedResource>\n" + " </ItemGroup>\n\n" + " <ItemGroup>\n" + " <None Include=\"..\\..\\LICENSE.md\">\n" + " <Pack>True</Pack>\n" + " <PackagePath></PackagePath>\n" + " </None>\n" + " <None Include=\"Resources\\icon.png\">\n" + " <Pack>True</Pack>\n" + " <PackagePath></PackagePath>\n" + " </None>\n" + " </ItemGroup>\n\n" + "</Project>\n"; final Pattern pattern = Pattern.compile(regex, Pattern.MULTILINE); final Matcher matcher = pattern.matcher(string); while (matcher.find()) { System.out.println("Full match: " + matcher.group(0)); for (int i = 1; i <= matcher.groupCount(); i++) { System.out.println("Group " + i + ": " + matcher.group(i)); } } } }

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 Java, please visit: https://docs.oracle.com/javase/7/docs/api/java/util/regex/Pattern.html