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 = "(?i)(?<=\")\\s*(?:https?)?:\\/\\/[^\"]+\\/(?=[^\"]*logo)[^\"]*(?:png|jpe?g|gif|tiff)\\s*(?=\")"; final String string = "<link rel=\"icon\" href=\"https://diabsolut.com/wp-content/uploads/2018/02/D-Logo-150x150.png\" sizes=\"32x32\">\n" + "<link rel=\"icon\" href=\"https://diabsolut.com/wp-content/uploads/2018/02/D-Logo.png\" sizes=\"192x192\">\n" + "<link rel=\"apple-touch-icon-precomposed\" href=\"https://diabsolut.com/wp-content/uploads/2018/02/D-Logo.png\">\n" + "<meta name=\"msapplication-TileImage\" content=\"https://diabsolut.com/wp-content/uploads/2018/02/D-Logo.png\">\n" + "<img width=\"200\" height=\"147\" src=\"https://diabsolut.com/wp-content/uploads/2017/05/Diabsolut-logo-01-e1496083111444.png\" class=\"attachment-large size-large\" alt=\"\">\n" + "<img src=\"https://diabsolut.com/wp-content/uploads/2019/03/White-FSM-logo.png\" width=\"330\" height=\"215\" data-no-retina=\"\" style=\"\">\n\n" + "<img src=\"https://diabsolut.com/wp-content/uploads/2017/05/Diabsolut-Cloud-Logo-Web-1.png\" width=\"277\" height=\"81\" data-no-retina=\"\" style=\"height: 100%; width: 100%; text-align: left; line-height: 16px; letter-spacing: 0px; font-weight: 300; font-size: 12px; border-color: rgb(255, 255, 255); border-style: none; margin: 0px; border-radius: 0px; padding: 0px;\" data-stylerecorder=\"true\"> \n\n" + "<img width=\"300\" height=\"179\" src=\"https://diabsolut.com/wp-content/uploads/2017/05/Watershed-CI-Logo-300x179.png\" class=\"attachment-medium size-medium\" alt=\"\" srcset=\"https://diabsolut.com/wp-content/uploads/2017/05/Watershed-CI-Logo-300x179.png 300w, https://diabsolut.com/wp-content/uploads/2017/05/Watershed-CI-Logo.png 350w\" sizes=\"(max-width: 300px) 100vw, 300px\"></a></div><h4 style=\"text-align: center\" class=\"vc_custom_heading vc_custom_1508180231294\">Consulting Solutions</h4>\n" + "logout"; 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