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

/
/
gm

Test String

Code Generator

Generated Code

# coding=utf8 # the above tag defines encoding for this document and is for Python 2.x compatibility import re regex = r"^(?:[a-zA-Z0-9+\/=-]{1,76}[\r|\n|\r\n]?)+" test_str = (" Login Register \n" "PHP Classes\n" "File: test/sample/message.eml\n" " Search \n" "Search\n" " Search All class groups All class groups Latest entries Latest entries Top 10 charts Top 10 charts Blog Blog Forums Forums Shop Shop Help Help \n" "Recommend this page to a friend!\n" " Classes of Manuel Lemos > PHP MIME Email Message Parser > test/sample/message.eml > Download \n" "File: test/sample/message.eml\n" "Role: Auxiliary data\n" "Content type: text/plain\n" "Description: Sample MIME message file used by the example script\n" "Class: PHP MIME Email Message Parser\n" "Decode MIME e-mail messages\n" "Author: By Manuel Lemos\n" "Last change: \n" "Date: 14 years ago\n" "Size: 9,051 bytes\n" " \n" " \n" "Contents\n" "Class file image Download\n" "Return-Path: <mlemos@acm.org>\n" "To: Manuel Lemos <mlemos@linux.local>\n" "Subject: Testing Manuel Lemos' MIME E-mail composing and sending PHP class: HTML message\n" "From: mlemos <mlemos@acm.org>\n" "Reply-To: mlemos <mlemos@acm.org>\n" "Sender: mlemos@acm.org\n" "X-Mailer: http://www.phpclasses.org/mimemessage $Revision: 1.63 $ (mail)\n" "MIME-Version: 1.0\n" "Content-Type: multipart/mixed; boundary=\"652b8c4dcb00cdcdda1e16af36781caf\"\n" "Message-ID: <20050430192829.0489.mlemos@acm.org>\n" "Date: Sat, 30 Apr 2005 19:28:29 -0300\n\n\n" "--652b8c4dcb00cdcdda1e16af36781caf\n" "Content-Type: multipart/related; boundary=\"6a82fb459dcaacd40ab3404529e808dc\"\n\n\n" "--6a82fb459dcaacd40ab3404529e808dc\n" "Content-Type: multipart/alternative; boundary=\"69c1683a3ee16ef7cf16edd700694a2f\"\n\n\n" "--69c1683a3ee16ef7cf16edd700694a2f\n" "Content-Type: text/plain; charset=ISO-8859-1\n" "Content-Transfer-Encoding: quoted-printable\n\n" "This is an HTML message. Please use an HTML capable mail program to read\n" "this message.\n\n" "--69c1683a3ee16ef7cf16edd700694a2f\n" "Content-Type: text/html; charset=ISO-8859-1\n" "Content-Transfer-Encoding: quoted-printable\n\n" "<html>\n" "<head>\n" "<title>Testing Manuel Lemos' MIME E-mail composing and sending PHP class: H=\n" "TML message</title>\n" "<style type=3D\"text/css\"><!--\n" "body { color: black ; font-family: arial, helvetica, sans-serif ; backgroun=\n" "d-color: #A3C5CC }\n" "A:link, A:visited, A:active { text-decoration: underline }\n" "--></style>\n" "</head>\n" "<body>\n" "<table background=3D\"cid:4c837ed463ad29c820668e835a270e8a.gif\" width=3D\"100=\n" "%\">\n" "<tr>\n" "<td>\n" "<center><h1>Testing Manuel Lemos' MIME E-mail composing and sending PHP cla=\n" "ss: HTML message</h1></center>\n" "<hr>\n" "<P>Hello Manuel,<br><br>\n" "This message is just to let you know that the <a href=3D\"http://www.phpclas=\n" "ses.org/mimemessage\">MIME E-mail message composing and sending PHP class</a=\n" "> is working as expected.<br><br>\n" "<center><h2>Here is an image embedded in a message as a separate part:</h2>=\n" "</center>\n" "<center><img src=3D\"cid:ae0357e57f04b8347f7621662cb63855.gif\"></center>Than=\n" "k you,<br>\n" "mlemos</p>\n" "</td>\n" "</tr>\n" "</table>\n" "</body>\n" "</html>\n" "--69c1683a3ee16ef7cf16edd700694a2f--\n\n" "--6a82fb459dcaacd40ab3404529e808dc\n" "Content-Type: image/gif; name=\"logo.gif\"\n" "Content-Transfer-Encoding: base64\n" "Content-Disposition: inline; filename=\"logo.gif\"\n" "Content-ID: <ae0357e57f04b8347f7621662cb63855.gif>\n\n" "R0lGODlhlgAjAPMJAAAAAAAA/y8vLz8/P19fX19f339/f4+Pj4+Pz7+/v///////////////////\n" "/////yH5BAEAAAkALAAAAACWACMAQwT+MMlJq7046827/2AoHYChGAChAkBylgKgKClFyEl6xDMg\n" "qLFBj3C5uXKplVAxIOxkA8BhdFCpDlMK1urMTrZWbAV8tVS5YsxtxmZHBVOSCcW9zaXyNhslVcto\n" "RBp5NQYxLAYGLi8oSwoJBlE+BiSNj5E/PDQsmy4pAJWQLAKJY5+hXhZ2dDYldFWtNSFPiXssXnZR\n" "k5+1pjpBiDMJUXG/Jo7DI4eKfMSmxsJ9GAUB1NXW19jZ2tvc3d7f4OHi2AgZN5vom1kk6F7s6u/p\n" "m3Ab7AOIiCxOyZuBIv8AOeTJIaYQjiR/kKTr5GQNE3pYSjCJ9mUXClRUsLxaZGciC0X+OlpoOuQo\n" "ZKdNJnIoKfnxRUQh6FLG0iLxIoYnJd0JEKISJyAQDodp3EUDC48oDnUY7HFI3wEDRjzycQJVZCQT\n" "Ol7NK+G0qgtkAcOKHUu2rNmzYTVqRMt2bB49bHompSchqg6HcGeANSMxr8sEa2y2HexnSEUTuWri\n" "SSbkYh7BgGVAnhB1b2REibESYaRoBgqIMYx59tFM9AvQffVG49P5NMZkMlHKhJPJb0knmSKZ6kSX\n" "JtbeF3Am7ocok6c7cM7pU5xcXiJJETUz16qPrzEfaFgZpvzn7h86YV5r/1mxXeAUMVyEIpnVUGpN\n" "RlG2ka9b3lP3pm2l6u7P+l/YLj3+RlEHbz1C0kRxSITQaAcilVBMEzmkkEQO8oSOBNg9SN+AX6hV\n" "z1pjgJiAhwCRsY8ZIp6xj1ruqCgeGeKNGEZwLnIwzTg45qjjjjz2GEA5hAUp5JBEFmnkkSCoWEcZ\n" "X8yohZNK1pFGPQS4hx0qNSLJlk9wCQORYu5QiMd7bUzGVyNlRiOHSlpuKdGEItHQ3HZ18beRRyws\n" "YSY/waDTiHf/tWlWUBAJiMJ1/Z0XXU7N0FnREpKM4NChCgbyRDq9XYpOplaKopN9NMkDnBbG+UMC\n" "QwLWIeaiglES6AjGARcPHCWoVAiatcTnGTABZoLPaPG1phccPv366mEvWEFSLnj+2QaonECwcJt/\n" "e1Zw3lJvVMmftBdVNQS3UngLCA85YHIQOy6JO9N4eZW7KJwtOUZmGwOMWqejwVW6RQzaikRHX3yI\n" "osKhDAq8wmnKSmdMwNidSOof9ZG2DoV0RfTVmLFtGmNk+CoZna0HQnPHS3AhRbIeDpqmR09E0bsu\n" "soeaw994z+rwQVInvqLenBftYjLOVphLFHhV9qsnez8AEUbQRgO737AxChjmyANxuEFHSGi7hFCV\n" "4jxLst2N8sRJYU+SHiAKjlmCgz2IffbLI5aaQR71hnkxq1ZfHSfKata6YDCJDMAQwY7wOgzhjxgj\n" "VFQnKB5uX4mr9qJ79pann+VcfcSzsSCd2mw5scqRRvlQ6TgcUelYhu75iPE4JejrsJOFQAG01277\n" "7bjnrvvuvPfu++/ABy887hfc6OPxyCevPDdAVoDA89BHL/301Fdv/fXYZ6/99tx3Pz0FEQAAOw==\n\n" "--6a82fb459dcaacd40ab3404529e808dc\n" "Content-Type: image/gif; name=\"background.gif\"\n" "Content-Transfer-Encoding: base64\n" "Content-Disposition: inline; filename=\"background.gif\"\n" "Content-ID: <4c837ed463ad29c820668e835a270e8a.gif>\n\n" "R0lGODlh+wHCAPMAAKPFzKLEy6HDyqHCyaDByJ/Ax56/xp2+xZ28xJy7w5u6wpq5wZm4wJm3v5i2\n" "vpe1vSwAAAAA+wHCAEME/hDISau9OOvNu/9gKI5kaZ5oqq5s675wLM90bd94ru987//AoHBILBqP\n" "yKRyyWw6n9CodEqtWq+gwSHReHgfjobY8X00FIc019tIHAYS7dqcQCDm3vC4fD4QAhUBBFsMZF8O\n" "hnkLCAYFW11tb1iTlJWWOXJdZZtmC24Eg3hgYntfbXainJ2fgBSZbG5wFAG0E6+RoAZ3CbwJCgya\n" "p3cMbAyevQcFAgMGCcRmxr1uyszOxQq+wF4MdcPFx7zJApfk5eYhr3SSGemRsu3dc+4iAqELhZwO\n" "0X6hkHUHCBRoGtUg0RkEAAUeKhhGAcICBQIODIPooIEBzCTmKcjGYSNd/go3VvQo65zJkyhTqlzJ\n" "sqXLlzBjypxJs6bNmzhz6tzJs6fPn0CDCh1KtKjRo0iTKl3KtKnTp1CXBhhAwECaq1gPNCIwANDU\n" "qmkMcG311apWULmyZt3alcPXAma1FgAlgCxVq2LbRt3LF0Y7hwWoEjLEDZUmff8AOjMkTB5gwYu3\n" "JbhIQUDEZw+4+aE1aNc0R2vcDYjoDBgpBoUDj95yzzRqbH7qgW4t5vUnAfVAoj7NwOOf1QloN7Ad\n" "u1Xf41b+IlCNsa6rR7DWwTPccTnG5sYvCEKwgPGiZI64A9OsK/Q/BM/0YfuFz13VOwsULLhHps+f\n" "98Hl0zeDRk0X9Qih/vLPWPjFN197aPyB3IJVBLDMdc5t4OB1A0QowYQQ0vIgdilgyGEgG1roYV0j\n" "GufhhyBSWGF2s2yIYosqWsjgjDTWaOONOOao44489ujjj0AGKeSQRBZp5JFIJqnkkkw26eSTUMJU\n" "llpYseXVXWGNdSGWZ6EVF5VWukUVXFdtRUCEU+bFYpRslqNcYKHgk1k8hxWWxjCM0VkdnINJRtkE\n" "lqH3hWZ/CKJYOBBBJxppu/FWh2qzNUrcmQRE6lpvt+UWUKPD9cbIb5bWhmlxbbL5JoUywiMddHRQ\n" "x591GWqwXXdsfJeoeMO5UZ4/AaaHKXv1xVKgfghuNuyB9fUHHYAA/u2CEIHlGbiffWuWyuSJMmKA\n" "bXbbbtuhi9kCUOIEJY57oYsraoduuOfGWO2J6Vor77z01mvvvfjmq+++/Pbr778AByzwwAQXbPDB\n" "CCfcZDobldLRVfLEEgerjQ1EEEemJMiioZEdkggYizSiqMQKl5wCw6qswg+rDTvc6h0Wq9KAJ5tV\n" "oGpJF9YysXn8lCfNL8HE88xw4EyzTDNDR4MMNUhfk40mhXkDTdHimHzjzRpgDcB0MEeHswf1sCZn\n" "GfrQDMrIAYZEkEEOJTQRQweBp5FIDTGCEUiHYWwRXHOPMpLdVgcu+OCEF2744YgnrvjijDfu+OOQ\n" "Ry755JRXbvnl/phnrvnmnHfu+eegZ57RAqSUzptv75E+M+Bb66L6InZwZ7rpr31aLQBhb2pap548\n" "e7TsIX8dOr/pIIZQQphFHfGqEbtq/J2/DDrZ13Ga0jt8h/XX9TxvfRmmuPVUatb34INCplxakjtm\n" "XOQ7aP74c+k1fE4MD7fefvxBbLEeLldsyq/4o9ZzHOOHylBFS7f4RJxQMx/8MeB4ggIDA02ziLno\n" "wlfGoOByKnUAhZQNWfkzwAXzMEExVFB+86NJ/TDVC4SIZRzFs5Ni5OQ/p7XwLOOwQDXSswgFiYuD\n" "Z4GMP8AjtvGgJk9aYU2davdCeyzRU2LpBwkb2KjvWCU4T/TN/u1S+BKtYUBrXFue8DYQKFoVAzXa\n" "eJh/XiYPpZEOFhAMTnzkk8aQWQU+c7yHJkIGkGd4SkDhMJ9i5qMAOu4RAWfiYk1yxwvfaYCRA8oh\n" "JF14x0bGhgSyaZY07JCMRDLyWWnxTOyc1UmweMaSL5zSKf/xQgnk5lA3TCWWVunCRCrylrjMpS53\n" "ycte+vKXwAymMIdJzGIa85jITKYyl8nMZjrzmdCMpjSnSc1qWvOa2MymvkY3u9IxMReyW92fuLm6\n" "2Kmum53SIgZyxx7e9C423AyeNnkUw8RsSnqumsfWKKYnCdozen6iHiGsF483gkF7PIND96oUP7KE\n" "73zteyj8/tK3JfGVqaHkkmhYMDrPJqzwfjRUlij4hzE4ds1pdGSMxgYYjAQZEBRtSeDKSmMMEGYG\n" "ghjU4+osGEF9ZNCEG3SEB2s6LTSIsKcl3CkKO2qEj24Sh/ucw/NmmCdXQQMbsbSlzZoGMkSSBYh5\n" "kWIkEhWc3aARiVc0qE+hSCklkvCbUpQgFTWYRCy+la1bZGoQvHgBMPIznyT7QBkNgsY05m+NNSQa\n" "Lwx6ijvJsZB69IIdB5nHOjKij9twCCAVGJ7HGlKyiMyhXo0wyUtmoLS2LK0ID+XIEWRys5ycyzg+\n" "yQ9TtjB2lpyLbZ8qy91mVZK+ReWZVCkNVmp1tMhNrnKX/svc5jr3udCNrnSnS93qWve62M2udrfL\n" "3e5697vgDa94x0ve8pr3vOhNr3rXy972uve98I2vfOdLXxrBS0Uv8lZGUaUh/OKXXRmAV7jMVV+X\n" "QLK4vD0TaoHLWq1UEsEJFu0FXknLh3iyM5EssEtQlrK98ZN5QbNqyl71pwqEza752MfZEqrhljg1\n" "pYMKkBh3FuKTXtUX+LupMkwcETNCA40D6QNiA3tfdunXAkdOEX+1Ba68tjiqLbVOnKp60oNAam6J\n" "fcyUvTYLAnDHOw8Jjx7Js71YTKWzxX1IV76iyayuWTCwDSIgKJxmqLI5zmp6sg5ZNdV7bkPGQWYh\n" "0EzR/s8+A1THEt6hIrx6IbByRawKHKjfpEfExVREpUEdzKX3dJe5UaQ6UdT0p18VGCfPF2X8S4QD\n" "QgaamI24hi1TtTxZyuVZ6AzK6gBnIbE66DmhImlzxAYouUq0XQ+oUhG039P+rAZgG7u1erYFyy6W\n" "Tt85ddkmHak3PWVaWuePAC9F4Mh6dgdjB/A8tCqbscUxWLmumxp8jsa5A5RuY7xbwtHGtT+Phz69\n" "nGo0WC60DPt9u0AljxWG8kylh9hsRKw1jbiwx24cDsUKSRwYFPdIq2347NoWkSEAKnG++brnGes7\n" "sYH1QPVqVdDsOZZXUlN2WYO1soCA9JBoScjNQdvs/n3fKXaxYefOH9BDfD+Z5Db78Dv+WuWUd4Bj\n" "YwPDx1bNiI03BoO7yRi9CzJBBLlQdj5tTbKIOFQqikHjruN6Bovlw5GnXZxjtMXbZ01O2NnhdawL\n" "ASOFw8BIxpOSuutUYWfmBjW0U1S+gczhqy0Wzuhmd7Ur5RYW/01Tz3dKcpYVl/Isrs2jBSyZJ4H7\n" "LIq+4VYUL2NZaCMgQiY1LXSjFH09wWexvovGvvawX2q+d8/73vv+98APvvCHT/ziG//4yE++8pfP\n" "/OY7//nQj770p0/96lv/+tjPvva3z/3ue//74A+/+MdP/vKb//zoT7/6e3Lf/3KryTDKUPvdBQIB\n" "/q+JwOuPwYEhbFzcYDjDuPN/lARL/FdLRlcZwdUNnTRbGAZt+fcCHCYzGqd0NJZtrsYJFjFGJ2ZQ\n" "m1A2kcZiD+gXLKNsMMZsTQdiFvg/IJUID7RjldFjhAVkGaM/6lASRfYu8KcuS6aDO4hkOfh7p7Jl\n" "bBRlVxYSWSZlfVKDXfZltRJmADFmulJmb3BmBJhbb9YZp1RLV9hmwtUWdBZhnYeFCaZ7Rxdv/5Q8\n" "gKaCvNBrQ0hCZxhjLhgHXEV1PiQIjhBEkDZT6VFSmkFWhbBppMZBljZqVtZpIUGIqCNqevMYlhdf\n" "qEYKslZ10zZibbgQDkN1IndyTkcLxiFTulZI/muYRsrjbKA4bNYwNR1nPsn2K6J4PKdYbKXYbSM3\n" "bSQVeWdybWwIa9Rmi0b3FwUEKAcUU+MGTr4AivP2hGSgbqDIbjDobssIb1IlbzSEbslob894gGUY\n" "jYkxeyf3GABnhAK3jeTDYxE0J5uRcEtjdYUnaoMXHStGGxlnNxs4cYgARRt3Y8UobB5XVhhXjyTR\n" "e0jnbfoURkGzDh+wcquACmqFUDD3iiw0LZFmczhmWTknkZ9FdK5IDH0GdArWGaB4kUXHewEpbSZH\n" "kLX2AVA3dVPHamgjNQ8XZG0Ddl2XLF9HOmF3RPmTKGV3IGdXdWl3k2zXiPBVd3nXV3PHOkRpgk5A\n" "lYlgg2F8Fw3WlnZW9HiCB2Q0Y3ic8k2Kl5V4JQhUiXgWFgqUh1e9h3mcpy2epxdm+XnjQ1EiMHoQ\n" "pVtogiWuV3urBxGod4Xnw41huJfjKHvtg3t8GYKEWZiGeZiImZiKuZiM2ZiO+ZiQGZmSOZmUWZmW\n" "eZmYmZmauZmc2ZlCEQEAOw==\n\n" "--6a82fb459dcaacd40ab3404529e808dc--\n\n" "--652b8c4dcb00cdcdda1e16af36781caf\n" "Content-Type: text/plain; name=\"attachment.txt\"\n" "Content-Transfer-Encoding: base64\n" "Content-Disposition: attachment; filename=\"attachment.txt\"\n\n" "VGhpcyBpcyBqdXN0IGEgcGxhaW4gdGV4dCBhdHRhY2htZW50IGZpbGUgbmFtZWQgYXR0YWNobWVu\n" "dC50eHQgLg==\n\n" "--652b8c4dcb00cdcdda1e16af36781caf--\n\n\n" " \n" " Advertise on this site Advertise On This Site Site map Site Map Newsletter Newsletter Statistics Statistics Site tips Site Tips Privacy policy Privacy Policy Contact Contact \n" "Icontem\n" "Copyright (c) Icontem 1999-2021\n" "For more information send a message to info at phpclasses dot org.") matches = re.finditer(regex, test_str, re.MULTILINE) 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