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
  • Match everything enclosed
    (?:...)
  • Capture everything enclosed
    (...)
  • 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

Substitution

Processing...

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 = "\\s(([a-zA-Z]+\\-[a-zA-Z]+|[a-zA-Z]+)\\.)"; final String string = "<p>With consumers becoming more and more health-conscious by the minute, the wearable fitness tracker market is ever-expanding.</p>\n" + "<p>So, to cut through the clutter, we created a lifestyle video series and an interactive kiosk experience at Best Buy, where we were able to inform and educate consumers about Jawbone’s Up products right there at point of sale.</p>\n" + "<p>By arming consumers with the knowledge on how to improve their personal physical fitness, they’re able to make informed decisions with the push of a button. As part of the experience, visually stimulating films helped people easily understand each product’s features and benefits as well as identify which product best fit their needs.</p>\n" + "<p>The lifestyle and product demonstration films within the interactive experience were also used across social media, the Jawbone website, and as TV spots in two countries.</p>\n" + "<div class=\"image\"><a href=\"http://goldenarm.com/staging/wp-content/uploads/2015/06/UpKiosk.jpg\"><img class=\"aligncenter wp-image-1156 size-large\" src=\"http://goldenarm.com/staging/wp-content/uploads/2015/06/UpKiosk-1024x643.jpg\" alt=\"\" width=\"1024\" height=\"643\"></a><img class=\"aligncenter wp-image-1348 size-large\" src=\"http://goldenarm.com/staging/wp-content/uploads/2015/06/6.-youpush-1600px-1024x576ABC.jpg\" alt=\"\" width=\"1024\" height=\"576\"></div>\n" + "<p class=\"work-page__video_container\"><div class=\"video-embed\"><iframe src=\"https://player.vimeo.com/video/122136552\" width=\"500\" height=\"281\" frameborder=\"0\" allowfullscreen=\"allowfullscreen\"></iframe></div><br>\n" + "<div class=\"video-embed\"><iframe src=\"https://player.vimeo.com/video/122136232\" width=\"500\" height=\"281\" frameborder=\"0\" allowfullscreen=\"allowfullscreen\"></iframe></div></p>\n" + "<div class=\"image\"><a style=\"font-size: 20px;\" href=\"http://goldenarm.com/staging/wp-content/uploads/2015/06/Screen-Shot-2015-06-23-at-2.55.39-PM.png\"><img class=\"alignnone size-full wp-image-857\" src=\"http://goldenarm.com/staging/wp-content/uploads/2015/06/Screen-Shot-2015-06-23-at-2.55.39-PM.png\" alt=\"Screen Shot 2015-06-23 at 2.55.39 PM\" width=\"639\" height=\"638\"></a></div>"; final String subst = "&nbsp;$1"; final Pattern pattern = Pattern.compile(regex); final Matcher matcher = pattern.matcher(string); // The substituted value will be contained in the result variable final String result = matcher.replaceAll(subst); System.out.println("Substitution result: " + result); } }

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