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 = "^(?:[\\w+/=-]{76}\\R)+[\\w+/=-]{1,76}"; final String string = " 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."; 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