Regular Expressions 101

Save & Share

  • Regex Version: ver. 1
  • 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

package main import ( "regexp" "fmt" ) func main() { var re = regexp.MustCompile(`\"locId\":\"(?<locId>[^\"]*)\",\"ip\":\"[^\"]*\",\"hostName\":\"[^\"]*\",\"macaddress\":\"(?<macaddress>[^\"]*)\"`) var str = `{"bdy":{"msg":"NitrosApplication_OnLaunched event triggered.","metricName":"AppStart","metricValue":"NitrosApplication_OnLaunched","measuredTime":"00:00:00.7181610"},"hdr":{"level":"Information","timestamp":"2017-03-17T15:00:55.9692895Z","lineNum":0,"userId":"a211ba03eb3aa1","loc":"Store","locId":"0775","ip":"10.434.24.4","hostName":"W-W10ME-7534513","macaddress":"00-16-7F-EE-DD-17","eventid":0,"appVersion":"10.0.2","appName":"L"},"ver":"0.1"} {"bdy":{"msg":"Background Task 'DevicePowerCheckBackgroundTask' is Running..."},"hdr":{"level":"Information","timestamp":"2017-03-17T15:00:55.842Z","fxsrc":"Run","lineNum":53,"loc":"Store","locId":"0320","ip":"10.439.3.11","hostName":"K-W10ME-054232","macaddress":"00-13-7F-13-33-29","eventid":0,"appVersion":"3.0.2","appName":"L"},"ver":"0.1"} {"bdy":{"msg":"SplashPage loaded on back click.","metricName":"PageLoad","metricValue":"SplashPage","measuredTime":"00:00:00.0006669"},"hdr":{"level":"Information","timestamp":"2017-03-17T15:00:55.3022117Z","lineNum":0,"loc":"Store","locId":"0466","ip":"10.111.11.7","hostName":"K-W10ME-3727099","macaddress":"00-15-7E-GE-D2-11","eventid":0,"appVersion":"16.2.0","appName":"L"},"ver":"0.1"}` for i, match := range re.FindAllString(str, -1) { fmt.Println(match, "found at index", 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 Golang, please visit: https://golang.org/pkg/regexp/