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

/
/
gi

Test String

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"https?:\/\/(youtu\.be|(www\.|m\.)?youtube(-nocookie)?\.com)(?P<viddeo_id>\/(.*)([?&]v=[a-zA-Z0-9_-]{11})|((\/attribution|\/oembed).*(v%3D[a-zA-Z0-9_-]{11}))|(\/shorts\/[a-zA-Z0-9_-]{11})|(\/embed\/[a-zA-Z0-9_-]{11})|(\/v\/[a-zA-Z0-9_-]{11})|((\/user)(\/.+1\/)([a-zA-Z0-9_-]{11}))|(\/e\/[a-zA-Z0-9_-]{11})|(\/live\/[a-zA-Z0-9_-]{11})|\/watch\/[a-zA-Z0-9_-]{11}|\/[a-zA-Z0-9_-]{11})" test_str = ("http://www.youtube.com/watch?v=0zM3nApSvMg&feature=feedrec_grec_index\n" "http://www.youtube.com/user/IngridMichaelsonVEVO#p/a/u/1/QdK8U-VIH_o\n" "http://www.youtube.com/v/0zM3nApSvMg?fs=1&amp;hl=en_US&amp;rel=0\n" "http://www.youtube.com/watch?v=0zM3nApSvMg#t=0m10s\n" "http://www.youtube.com/embed/0zM3nApSvMg?rel=0\n" "http://www.youtube.com/watch?v=0zM3nApSvMg\n" "http://youtu.be/0zM3nApSvMg\n" "https://youtube.com/shorts/0dPkkQeRwTI?feature=share\n" "https://youtube.com/shorts/0dPkkQeRwTI\n\n\n" "http://www.youtube.com/watch?v=-wtIMTCHWuI\n" "http://youtube.com/watch?v=-wtIMTCHWuI\n" "http://m.youtube.com/watch?v=-wtIMTCHWuI\n" "https://www.youtube.com/watch?v=lalOy8Mbfdc\n" "https://youtube.com/watch?v=lalOy8Mbfdc\n" "https://m.youtube.com/watch?v=lalOy8Mbfdc\n\n" "http://www.youtube.com/watch?v=yZv2daTWRZU&feature=em-uploademail\n" "http://youtube.com/watch?v=yZv2daTWRZU&feature=em-uploademail\n" "http://m.youtube.com/watch?v=yZv2daTWRZU&feature=em-uploademail\n" "https://www.youtube.com/watch?v=yZv2daTWRZU&feature=em-uploademail\n" "https://youtube.com/watch?v=yZv2daTWRZU&feature=em-uploademail\n" "https://m.youtube.com/watch?v=yZv2daTWRZU&feature=em-uploademail\n\n" "http://www.youtube.com/watch?v=0zM3nApSvMg&feature=feedrec_grec_index\n" "http://youtube.com/watch?v=0zM3nApSvMg&feature=feedrec_grec_index\n" "http://m.youtube.com/watch?v=0zM3nApSvMg&feature=feedrec_grec_index\n" "https://www.youtube.com/watch?v=0zM3nApSvMg&feature=feedrec_grec_index\n" "https://youtube.com/watch?v=0zM3nApSvMg&feature=feedrec_grec_index\n" "https://m.youtube.com/watch?v=0zM3nApSvMg&feature=feedrec_grec_index\n\n" "http://www.youtube.com/watch?v=0zM3nApSvMg#t=0m10s\n" "http://youtube.com/watch?v=0zM3nApSvMg#t=0m10s\n" "http://m.youtube.com/watch?v=0zM3nApSvMg#t=0m10s\n" "https://www.youtube.com/watch?v=0zM3nApSvMg#t=0m10s\n" "https://youtube.com/watch?v=0zM3nApSvMg#t=0m10s\n" "https://m.youtube.com/watch?v=0zM3nApSvMg#t=0m10s\n\n" "http://www.youtube.com/watch?v=cKZDdG9FTKY&feature=channel\n" "http://youtube.com/watch?v=cKZDdG9FTKY&feature=channel\n" "http://m.youtube.com/watch?v=cKZDdG9FTKY&feature=channel\n" "https://www.youtube.com/watch?v=oTJRivZTMLs&feature=channel\n" "https://youtube.com/watch?v=oTJRivZTMLs&feature=channel\n" "https://m.youtube.com/watch?v=oTJRivZTMLs&feature=channel\n\n" "http://www.youtube.com/watch?v=lalOy8Mbfdc&playnext_from=TL&videos=osPknwzXEas&feature=sub\n" "http://youtube.com/watch?v=lalOy8Mbfdc&playnext_from=TL&videos=osPknwzXEas&feature=sub\n" "http://m.youtube.com/watch?v=lalOy8Mbfdc&playnext_from=TL&videos=osPknwzXEas&feature=sub\n" "https://www.youtube.com/watch?v=lalOy8Mbfdc&playnext_from=TL&videos=osPknwzXEas&feature=sub\n" "https://youtube.com/watch?v=lalOy8Mbfdc&playnext_from=TL&videos=osPknwzXEas&feature=sub\n" "https://m.youtube.com/watch?v=lalOy8Mbfdc&playnext_from=TL&videos=osPknwzXEas&feature=sub\n\n" "http://www.youtube.com/watch?v=lalOy8Mbfdc&feature=youtu.be\n" "http://youtube.com/watch?v=lalOy8Mbfdc&feature=youtu.be\n" "http://m.youtube.com/watch?v=lalOy8Mbfdc&feature=youtu.be\n" "https://www.youtube.com/watch?v=lalOy8Mbfdc&feature=youtu.be\n" "https://youtube.com/watch?v=lalOy8Mbfdc&feature=youtu.be\n" "https://m.youtube.com/watch?v=lalOy8Mbfdc&feature=youtu.be\n\n" "http://www.youtube.com/watch?v=dQw4w9WgXcQ&feature=youtube_gdata_player\n" "http://youtube.com/watch?v=dQw4w9WgXcQ&feature=youtube_gdata_player\n" "http://m.youtube.com/watch?v=dQw4w9WgXcQ&feature=youtube_gdata_player\n" "https://www.youtube.com/watch?v=dQw4w9WgXcQ&feature=youtube_gdata_player\n" "https://youtube.com/watch?v=dQw4w9WgXcQ&feature=youtube_gdata_player\n" "https://m.youtube.com/watch?v=dQw4w9WgXcQ&feature=youtube_gdata_player\n\n" "http://www.youtube.com/watch?v=ishbTyLs6ps&list=PLGup6kBfcU7Le5laEaCLgTKtlDcxMqGxZ&index=106&shuffle=2655\n" "http://youtube.com/watch?v=ishbTyLs6ps&list=PLGup6kBfcU7Le5laEaCLgTKtlDcxMqGxZ&index=106&shuffle=2655\n" "http://m.youtube.com/watch?v=ishbTyLs6ps&list=PLGup6kBfcU7Le5laEaCLgTKtlDcxMqGxZ&index=106&shuffle=2655\n" "https://www.youtube.com/watch?v=ishbTyLs6ps&list=PLGup6kBfcU7Le5laEaCLgTKtlDcxMqGxZ&index=106&shuffle=2655\n" "https://youtube.com/watch?v=ishbTyLs6ps&list=PLGup6kBfcU7Le5laEaCLgTKtlDcxMqGxZ&index=106&shuffle=2655\n" "https://m.youtube.com/watch?v=ishbTyLs6ps&list=PLGup6kBfcU7Le5laEaCLgTKtlDcxMqGxZ&index=106&shuffle=2655\n\n" "http://www.youtube.com/watch?feature=player_embedded&v=dQw4w9WgXcQ\n" "http://youtube.com/watch?feature=player_embedded&v=dQw4w9WgXcQ\n" "http://m.youtube.com/watch?feature=player_embedded&v=dQw4w9WgXcQ\n" "https://www.youtube.com/watch?feature=player_embedded&v=dQw4w9WgXcQ\n" "https://youtube.com/watch?feature=player_embedded&v=dQw4w9WgXcQ\n" "https://m.youtube.com/watch?feature=player_embedded&v=dQw4w9WgXcQ\n\n" "http://www.youtube.com/watch?app=desktop&v=dQw4w9WgXcQ\n" "http://youtube.com/watch?app=desktop&v=dQw4w9WgXcQ\n" "http://m.youtube.com/watch?app=desktop&v=dQw4w9WgXcQ\n" "https://www.youtube.com/watch?app=desktop&v=dQw4w9WgXcQ\n" "https://youtube.com/watch?app=desktop&v=dQw4w9WgXcQ\n" "https://m.youtube.com/watch?app=desktop&v=dQw4w9WgXcQ\n\n\n" "http://www.youtube.com/watch/-wtIMTCHWuI\n" "http://youtube.com/watch/-wtIMTCHWuI\n" "http://m.youtube.com/watch/-wtIMTCHWuI\n" "https://www.youtube.com/watch/-wtIMTCHWuI\n" "https://youtube.com/watch/-wtIMTCHWuI\n" "https://m.youtube.com/watch/-wtIMTCHWuI\n\n" "http://www.youtube.com/watch/-wtIMTCHWuI?app=desktop\n" "http://youtube.com/watch/-wtIMTCHWuI?app=desktop\n" "http://m.youtube.com/watch/-wtIMTCHWuI?app=desktop\n" "https://www.youtube.com/watch/-wtIMTCHWuI?app=desktop\n" "https://youtube.com/watch/-wtIMTCHWuI?app=desktop\n" "https://m.youtube.com/watch/-wtIMTCHWuI?app=desktop\n\n\n" "http://www.youtube.com/v/dQw4w9WgXcQ\n" "http://youtube.com/v/dQw4w9WgXcQ\n" "http://m.youtube.com/v/dQw4w9WgXcQ\n" "https://www.youtube.com/v/dQw4w9WgXcQ\n" "https://youtube.com/v/dQw4w9WgXcQ\n" "https://m.youtube.com/v/dQw4w9WgXcQ\n\n" "http://www.youtube.com/v/-wtIMTCHWuI?version=3&autohide=1\n" "http://youtube.com/v/-wtIMTCHWuI?version=3&autohide=1\n" "http://m.youtube.com/v/-wtIMTCHWuI?version=3&autohide=1\n" "https://www.youtube.com/v/-wtIMTCHWuI?version=3&autohide=1\n" "https://youtube.com/v/-wtIMTCHWuI?version=3&autohide=1\n" "https://m.youtube.com/v/-wtIMTCHWuI?version=3&autohide=1\n\n" "http://www.youtube.com/v/0zM3nApSvMg?fs=1&hl=en_US&rel=0\n" "http://youtube.com/v/0zM3nApSvMg?fs=1&hl=en_US&rel=0\n" "http://m.youtube.com/v/0zM3nApSvMg?fs=1&hl=en_US&rel=0\n" "https://www.youtube.com/v/0zM3nApSvMg?fs=1&amp;hl=en_US&amp;rel=0\n" "https://www.youtube.com/v/0zM3nApSvMg?fs=1&hl=en_US&rel=0\n" "https://youtube.com/v/0zM3nApSvMg?fs=1&hl=en_US&rel=0\n" "https://m.youtube.com/v/0zM3nApSvMg?fs=1&hl=en_US&rel=0\n\n" "http://www.youtube.com/v/dQw4w9WgXcQ?feature=youtube_gdata_player\n" "http://youtube.com/v/dQw4w9WgXcQ?feature=youtube_gdata_player\n" "http://m.youtube.com/v/dQw4w9WgXcQ?feature=youtube_gdata_player\n" "https://www.youtube.com/v/dQw4w9WgXcQ?feature=youtube_gdata_player\n" "https://youtube.com/v/dQw4w9WgXcQ?feature=youtube_gdata_player\n" "https://m.youtube.com/v/dQw4w9WgXcQ?feature=youtube_gdata_player\n\n\n" "http://youtu.be/-wtIMTCHWuI\n" "https://youtu.be/-wtIMTCHWuI\n\n" "http://youtu.be/dQw4w9WgXcQ?feature=youtube_gdata_player\n" "https://youtu.be/dQw4w9WgXcQ?feature=youtube_gdata_player\n\n" "http://youtu.be/oTJRivZTMLs?list=PLToa5JuFMsXTNkrLJbRlB--76IAOjRM9b\n" "https://youtu.be/oTJRivZTMLs?list=PLToa5JuFMsXTNkrLJbRlB--76IAOjRM9b\n\n" "http://youtu.be/oTJRivZTMLs&feature=channel\n" "https://youtu.be/oTJRivZTMLs&feature=channel\n\n" "http://youtu.be/lalOy8Mbfdc?t=1\n" "http://youtu.be/lalOy8Mbfdc?t=1s\n" "https://youtu.be/lalOy8Mbfdc?t=1\n" "https://youtu.be/lalOy8Mbfdc?t=1s\n\n" "http://youtu.be/M9bq_alk-sw?si=B_RZg_I-lLaa7UU-\n" "https://youtu.be/M9bq_alk-sw?si=B_RZg_I-lLaa7UU-\n\n\n" "http://www.youtube.com/embed/lalOy8Mbfdc\n" "http://youtube.com/embed/lalOy8Mbfdc\n" "http://m.youtube.com/embed/lalOy8Mbfdc\n" "https://www.youtube.com/embed/lalOy8Mbfdc\n" "https://youtube.com/embed/lalOy8Mbfdc\n" "https://m.youtube.com/embed/lalOy8Mbfdc\n\n" "http://www.youtube.com/embed/nas1rJpm7wY?rel=0\n" "http://youtube.com/embed/nas1rJpm7wY?rel=0\n" "http://m.youtube.com/embed/nas1rJpm7wY?rel=0\n" "https://www.youtube.com/embed/nas1rJpm7wY?rel=0\n" "https://youtube.com/embed/nas1rJpm7wY?rel=0\n" "https://m.youtube.com/embed/nas1rJpm7wY?rel=0\n\n\n" "http://www.youtube-nocookie.com/embed/lalOy8Mbfdc?rel=0\n" "https://www.youtube-nocookie.com/embed/lalOy8Mbfdc?rel=0\n\n\n" "http://www.youtube.com/e/dQw4w9WgXcQ\n" "http://youtube.com/e/dQw4w9WgXcQ\n" "http://m.youtube.com/e/dQw4w9WgXcQ\n" "https://www.youtube.com/e/dQw4w9WgXcQ\n" "https://youtube.com/e/dQw4w9WgXcQ\n" "https://m.youtube.com/e/dQw4w9WgXcQ\n\n\n" "http://www.youtube.com/shorts/j9rZxAF3C0I\n" "http://youtube.com/shorts/j9rZxAF3C0I\n" "http://m.youtube.com/shorts/j9rZxAF3C0I\n" "https://www.youtube.com/shorts/j9rZxAF3C0I\n" "https://youtube.com/shorts/j9rZxAF3C0I\n" "https://m.youtube.com/shorts/j9rZxAF3C0I\n\n" "http://www.youtube.com/shorts/j9rZxAF3C0I?app=desktop\n" "http://youtube.com/shorts/j9rZxAF3C0I?app=desktop\n" "http://m.youtube.com/shorts/j9rZxAF3C0I?app=desktop\n" "https://www.youtube.com/shorts/j9rZxAF3C0I?app=desktop\n" "https://youtube.com/shorts/j9rZxAF3C0I?app=desktop\n" "https://m.youtube.com/shorts/j9rZxAF3C0I?app=desktop\n\n\n" "http://www.youtube.com/live/8hBmepWUJoc\n" "http://youtube.com/live/8hBmepWUJoc\n" "http://m.youtube.com/live/8hBmepWUJoc\n" "https://www.youtube.com/live/8hBmepWUJoc\n" "https://youtube.com/live/8hBmepWUJoc\n" "https://m.youtube.com/live/8hBmepWUJoc\n\n" "http://www.youtube.com/live/8hBmepWUJoc?app=desktop\n" "http://youtube.com/live/8hBmepWUJoc?app=desktop\n" "http://m.youtube.com/live/8hBmepWUJoc?app=desktop\n" "https://www.youtube.com/live/8hBmepWUJoc?app=desktop\n" "https://youtube.com/live/8hBmepWUJoc?app=desktop\n" "https://m.youtube.com/live/8hBmepWUJoc?app=desktop\n\n" "http://www.youtube.com/oembed?url=http%3A//www.youtube.com/watch?v%3D-wtIMTCHWuI&format=json\n" "http://youtube.com/oembed?url=http%3A//www.youtube.com/watch?v%3D-wtIMTCHWuI&format=json\n" "http://m.youtube.com/oembed?url=http%3A//www.youtube.com/watch?v%3D-wtIMTCHWuI&format=json\n" "https://www.youtube.com/oembed?url=http%3A//www.youtube.com/watch?v%3D-wtIMTCHWuI&format=json\n" "https://youtube.com/oembed?url=http%3A//www.youtube.com/watch?v%3D-wtIMTCHWuI&format=json\n" "https://m.youtube.com/oembed?url=http%3A//www.youtube.com/watch?v%3D-wtIMTCHWuI&format=json\n\n\n" "http://www.youtube.com/attribution_link?a=JdfC0C9V6ZI&u=%2Fwatch%3Fv%3DEhxJLojIE_o%26feature%3Dshare\n" "http://youtube.com/attribution_link?a=JdfC0C9V6ZI&u=%2Fwatch%3Fv%3DEhxJLojIE_o%26feature%3Dshare\n" "http://m.youtube.com/attribution_link?a=JdfC0C9V6ZI&u=%2Fwatch%3Fv%3DEhxJLojIE_o%26feature%3Dshare\n" "https://www.youtube.com/attribution_link?a=JdfC0C9V6ZI&u=%2Fwatch%3Fv%3DEhxJLojIE_o%26feature%3Dshare\n" "https://youtube.com/attribution_link?a=JdfC0C9V6ZI&u=%2Fwatch%3Fv%3DEhxJLojIE_o%26feature%3Dshare\n" "https://m.youtube.com/attribution_link?a=JdfC0C9V6ZI&u=%2Fwatch%3Fv%3DEhxJLojIE_o%26feature%3Dshare\n\n" "http://www.youtube.com/attribution_link?a=8g8kPrPIi-ecwIsS&u=/watch%3Fv%3DyZv2daTWRZU%26feature%3Dem-uploademail\n" "http://youtube.com/attribution_link?a=8g8kPrPIi-ecwIsS&u=/watch%3Fv%3DyZv2daTWRZU%26feature%3Dem-uploademail\n" "http://m.youtube.com/attribution_link?a=8g8kPrPIi-ecwIsS&u=/watch%3Fv%3DyZv2daTWRZU%26feature%3Dem-uploademail\n" "https://www.youtube.com/attribution_link?a=8g8kPrPIi-ecwIsS&u=/watch%3Fv%3DyZv2daTWRZU%26feature%3Dem-uploademail\n" "https://youtube.com/attribution_link?a=8g8kPrPIi-ecwIsS&u=/watch%3Fv%3DyZv2daTWRZU%26feature%3Dem-uploademail\n" "https://m.youtube.com/attribution_link?a=8g8kPrPIi-ecwIsS&u=/watch%3Fv%3DyZv2daTWRZU%26feature%3Dem-uploademail") matches = re.finditer(regex, test_str, re.IGNORECASE) for matchNum, match in enumerate(matches, start=1): print ("Match {matchNum} was found at {start}-{end}: {match}".format(matchNum = matchNum, start = match.start(), end = match.end(), match = match.group())) for groupNum in range(0, len(match.groups())): groupNum = groupNum + 1 print ("Group {groupNum} found at {start}-{end}: {group}".format(groupNum = groupNum, start = match.start(groupNum), end = match.end(groupNum), group = match.group(groupNum))) # 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