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

# coding=utf8 # the above tag defines encoding for this document and is for Python 2.x compatibility import re regex = r"\s(([a-zA-Z]+\-[a-zA-Z]+|[a-zA-Z]+)\.)" test_str = ("<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>") subst = "&nbsp;$1" # You can manually specify the number of replacements by changing the 4th argument result = re.sub(regex, subst, test_str, 0) if result: print (result) # Note: for Python 2.7 compatibility, use ur"" to prefix the regex and u"" to prefix the test string and substitution.

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 Python, please visit: https://docs.python.org/3/library/re.html