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

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+)\\}\\}"; final String string = "\n" + "<!DOCTYPE html PUBLIC \"-//W3C//DTD XHTML 1.0 Transitional//EN\" \"http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd\">\n" + "<html lang=\"en\" xml:lang=\"en\" xmlns=\"http://www.w3.org/1999/xhtml\" xmlns:o=\"urn:schemas-microsoft-com:office:office\" xmlns:v=\"urn:schemas-microsoft-com:vml\">\n" + "<head>\n" + " <meta content=\"text/html; charset=UTF-8\" http-equiv=\"Content-Type\" />\n" + " <meta content=\"width=device-width, initial-scale=1.0\" name=\"viewport\" />\n" + " <meta name=\"x-apple-disable-message-reformatting\" /><!--[if mso]>\n" + " <meta http-equiv=\"X-UA-Compatible\" content=\"IE=edge\" />\n" + " <![endif]-->\n" + " <title>Scheduled Maintenance</title>\n" + " <style type=\"text/css\">/* === Custom Fonts === */\n" + " /* Add your fonts here via imports */\n\n" + " /* === Client Styles === */\n" + " #outlook a {padding: 0;}\n" + " .ReadMsgBody {width: 100%;} .ExternalClass {width: 100%;}\n" + " .ExternalClass, .ExternalClass p, .ExternalClass span, .ExternalClass font, .ExternalClass td, .ExternalClass div {line-height: 100%;} \n" + " body, table, td, p, a, li, blockquote {-ms-text-size-adjust: 100%; -webkit-text-size-adjust: 100%;}\n" + " table, td {mso-table-lspace: 0pt; mso-table-rspace: 0pt;}\n" + " img {-ms-interpolation-mode: bicubic;}\n\n" + " /* === Reset Styles === */\n" + " body, p, h1, h3 {margin: 0; padding: 0;}\n" + " img {border: 0; display: block; height: auto; line-height: 100%; max-width: 100%; outline: none; text-decoration: none;}\n" + " table, td {border-collapse: collapse}\n" + " body {height: 100% !important; margin: 0; padding: 0; width: 100% !important;}\n\n" + " /* === Page Structure === */\n" + " /*\n" + " Set the background color of your email. Light neutrals or your primary brand color are most common.\n" + " */\n" + " body {\n" + " background-color: #2C3E50; /* Edit */\n" + " }\n\n" + " /*\n" + " This optional section will be hidden in your email but the text will appear after the subject line. \n" + " */\n" + " #preheader {display: none !important; font-size: 1px; line-height: 1px; max-height: 0px; max-width: 0px; mso-hide: all !important; opacity: 0; overflow: hidden; visibility: hidden;}\n\n" + " /*\n" + " Set the background color, border and radius of your primary content area. White or light neutrals for the background-color are recommended.\n" + " */\n" + " .panel-container {\n" + " background-color: #E1F5FE; /* Edit */\n" + " border: 1px solid #eaebec; /* Edit */\n" + " border-collapse: separate;\n" + " border-radius: 2px; /* Edit */\n" + " }\n\n" + " /*\n" + " Set the horizontal padding of your content areas. Any changes should following the default spacing scale.\n" + " */ \n" + " #header, #footer {padding-left: 32px; padding-right: 32px;}\n" + " .panel-body {padding-left: 32px; padding-right: 32px;}\n\n" + " /*\n" + " Set the sizes of your spacer rows. Spacers are used for vertical padding. Any changes should following the default spacing scale.\n" + " */\n" + " .spacer-xxs, .spacer-xs, .spacer-sm, .spacer-md, .spacer-lg, .spacer-xl, .spacer-xxl {display: block; width: 100%;}\n" + " .spacer-xxs {height: 4px; line-height: 4px;}\n" + " .spacer-xs {height: 8px; line-height: 8px;}\n" + " .spacer-sm {height: 16px; line-height: 16px;}\n" + " .spacer-md {height: 24px; line-height: 24px;}\n" + " .spacer-lg {height: 32px; line-height: 32px;}\n" + " .spacer-xl {height: 40px; line-height: 40px;}\n" + " .spacer-xxl {height: 48px; line-height: 48px;}\n" + " \n" + " /* === Page Styles === */\n" + " /*\n" + " Set the font-family of your type. Classes should be set directly on the table cell for compatibility with older clients. Any changes should follow the default typography scale.\n" + " */\n" + " .headline-one, .headline-two, .headline-three, .heading, .subheading, .body, .caption, .button, .table-heading {\n" + " font-family: -apple-system,system-ui,BlinkMacSystemFont,\"Segoe UI\",Roboto,\"Helvetica Neue\",Arial,sans-serif; /* Edit */\n" + " font-style: normal;\n" + " font-variant: normal;\n" + " }\n" + " .headline-one {font-size: 32px; font-weight: 500; line-height: 40px;}\n" + " .headline-two {font-size: 24px; font-weight: 500; line-height: 32px;}\n" + " .headline-three {font-size: 20px; font-weight: 500; line-height: 24px;}\n" + " .heading {font-size: 16px; font-weight: 500; line-height: 24px;}\n" + " .subheading {font-size: 12px; font-weight: 700; line-height: 16px; text-transform: uppercase;}\n" + " .body {font-size: 14px; font-weight: 400; line-height: 20px;}\n" + " .caption {font-size: 12px; font-weight: 400; line-height: 16px;}\n" + " .table-heading {font-size: 10px; font-weight: 700; text-transform: uppercase;}\n\n" + " /*\n" + " Set the styles of your links.\n" + " */\n" + " a {color: inherit; font-weight: normal; text-decoration: underline;}\n\n" + " /*\n" + " Set the colors of your text.\n" + " */ \n" + " .text-primary {\n" + " color: #007bff; /* Edit */\n" + " }\n" + " .text-secondary {\n" + " color: #ECF0F1 ; /* Edit */\n" + " }\n" + " .text-black {\n" + " color: #000000; /* Edit */\n" + " }\n" + " .text-dark-gray {\n" + " color: #343a40; /* Edit */\n" + " }\n" + " .text-gray {\n" + " color: #6c757d; /* Edit */\n" + " }\n" + " .text-light-gray {\n" + " color: #f8f9fa; /* Edit */\n" + " }\n" + " .text-white {\n" + " color: #ffffff; /* Edit */\n" + " }\n" + " .text-success {\n" + " color: #28a745; /* Edit */\n" + " }\n" + " .text-danger {\n" + " color: #dc3545; /* Edit */\n" + " }\n" + " .text-warning {\n" + " color: #ffc107; /* Edit */\n" + " }\n" + " .text-info {\n" + " color: #17a2b8; /* Edit */\n" + " }\n\n" + " /*\n" + " Set the styles of your buttons. Each button requires a matching background.\n" + " */\n" + " .button-bg {\n" + " border-radius: 2px; /* Editable */\n" + " }\n" + " .button-bg-primary {\n" + " background-color: #007bff /* Editable */;\n" + " }\n" + " .button-bg-secondary {\n" + " background-color: #6c757d; /* Editable */\n" + " }\n" + " .button-bg-success {\n" + " background-color: #28a745; /* Editable */\n" + " }\n" + " .button-bg-danger {\n" + " background-color: #dc3545; /* Editable */\n" + " }\n" + " .button {\n" + " border-radius: 2px; /* Editable */\n" + " color: #ffffff; /* Editable */\n" + " display: inline-block;\n" + " font-size: 14px;\n" + " font-weight: 700; \n" + " padding: 10px 20px 10px;\n" + " text-decoration: none;\n" + " }\n" + " .button-primary {\n" + " border: 1px solid #007bff /* Editable */;\n" + " }\n" + " .button-secondary {\n" + " border: 1px solid #6c757d; /* Editable */\n" + " }\n" + " .button-success {\n" + " border: 1px solid #28a745; /* Editable */\n" + " } \n" + " .button-danger {\n" + " border: 1px solid #dc3545; /* Editable */\n" + " }\n\n" + " /*\n" + " Set the styles of your backgrounds.\n" + " */ \n" + " .bg {padding-left: 24px; padding-right: 24px;} \n" + " .bg-primary {\n" + " background-color: #007bff; /* Edit */\n" + " }\n" + " .bg-secondary {\n" + " background-color: #6c757d; /* Edit */\n" + " }\n" + " .bg-black {\n" + " background-color: #000000; /* Edit */\n" + " }\n" + " .bg-dark-gray {\n" + " background-color: #343a40; /* Edit */\n" + " }\n" + " .bg-gray {\n" + " background-color: #6c757d; /* Edit */\n" + " }\n" + " .bg-light-gray {\n" + " background-color: #f8f9fa; /* Edit */\n" + " }\n" + " .bg-white {\n" + " background-color: #ffffff; /* Edit */\n" + " }\n" + " .bg-success {\n" + " background-color: #28a745; /* Edit */\n" + " }\n" + " .bg-danger {\n" + " background-color: #dc3545; /* Edit */\n" + " }\n" + " .bg-warning {\n" + " background-color: #ffc107; /* Edit */\n" + " }\n" + " .bg-info {\n" + " background-color: #17a2b8; /* Edit */\n" + " }\n\n" + " /*\n" + " Set the styles of your tabular information. This class should not be set on tables with a role of presentation.\n" + " */\n" + " .table {min-width: 100%; width: 100%;}\n" + " .table td {\n" + " border-top: 1px solid #eaebec; /* Editable */\n" + " padding-bottom: 12px;\n" + " padding-left: 12px;\n" + " padding-right: 12px;\n" + " padding-top: 12px;\n" + " vertical-align: top;\n" + " }\n" + " \n" + " /*\n" + " Set the styles of your utility classes.\n" + " */\n" + " .address, .address a {color: inherit !important;}\n" + " .border-solid {\n" + " border-style: solid !important;\n" + " border-width: 2px !important; /* Edit */\n" + " border-color: #eaebec !important; /* Edit */\n" + " }\n" + " .divider {\n" + " border-bottom: 0px; \n" + " border-top: 1px solid #eaebec; /* Edit */\n" + " height: 1px; \n" + " line-height: 1px;\n" + " width: 100%;\n" + " } \n" + " .text-bold {font-weight: 700;}\n" + " .text-italic {font-style: italic;}\n" + " .text-uppercase {text-transform: uppercase;}\n" + " .text-underline {text-decoration: underline;}\n\n" + " @media only screen and (max-width: 599px) \n" + " {\n" + " /* === Client Styles === */ \n" + " body, table, td, p, a, li, blockquote {-webkit-text-size-adjust: none !important;}\n" + " body {min-width: 100% !important; width: 100% !important;}\n" + " center {padding-left: 12px !important; padding-right: 12px !important;}\n\n" + " /* === Page Structure === */\n" + " /*\n" + " Adjust sizes and spacing on mobile.\n" + " */\n" + " #email-container {max-width: 600px !important; width: 100% !important;}\n" + " #header, #footer {padding-left: 24px !important; padding-right: 24px !important;}\n" + " .panel-container {max-width: 600px !important; width: 100% !important;} \n" + " .panel-body {padding-left: 24px !important; padding-right: 24px !important;}\n" + " .column-responsive {display: block !important; padding-bottom: 24px !important; width:100% !important;}\n" + " .column-responsive img {width: auto !important;}\n" + " .column-responsive-last {padding-bottom: 0px !important;}\n" + " .column-responsive-gutter {display: none !important;}\n\n" + " /* === Page Styles === */\n" + " /*\n" + " Adjust sizes and spacing on mobile.\n" + " */\n" + " }\n" + " </style>\n" + " <!--[if gte mso 9]>\n" + " <xml>\n" + " <o:OfficeDocumentSettings>\n" + " <o:AllowPNG/>\n" + " <o:PixelsPerInch>96</o:PixelsPerInch>\n" + " </o:OfficeDocumentSettings>\n" + " </xml>\n" + " <![endif]--><!--[if mso]>\n" + " <xml xmlns:w=\"urn:schemas-microsoft-com:office:word\">\n" + " <w:WordDocument><w:AutoHyphenation/></w:WordDocument>\n" + " </xml>\n" + " <![endif]-->\n" + "</head>\n" + "<body style=\"background-color:#2C3E50;\">\n" + "<center><!-- Start Email Container -->\n\n" + "<table border=\"0\" cellpadding=\"0\" cellspacing=\"0\" id=\"email-container\" role=\"presentation\" width=\"600\" >\n" + " <tbody><!-- Start Preheader -->\n" + " <tr bgcolor=>\n" + " <td id=\"preheader\">SMS received</td>\n" + " </tr>\n" + " <!-- End Preheader -->\n" + " <tr>\n" + " <td class=\"spacer-lg\"></td>\n" + " </tr>\n" + " <tr>\n" + " <td id=\"email-body\" valign=\"top\"><!-- Start Panel Container -->\n" + " <table border=\"0\" cellpadding=\"0\" cellspacing=\"0\" class=\"panel-container\" role=\"presentation\" width=\"100%\" bgcolor=\"#E1F5FE\">\n" + " <tbody>\n" + " <tr>\n" + " <td class=\"spacer-lg\"></td>\n" + " </tr>\n" + " <!-- Start Header -->\n" + " <tr>\n" + " <td align=\"left\" id=\"header\"><a href=\"https://gem-car.com\"><img alt=\"Company\" border=\"0\" src=\"https://www.gem-car.com/images/stories/logo/gem-car-billing-software-automobile-garage.png\" /> </a></td> \n" + " </tr>\n" + " <tr>\n" + " <td align=\"left\" class=\"headline-two text-dark-gray\">{{Organization}}</td>\n" + " </tr>\n" + " <!-- End Header -->\n" + " <tr>\n" + " <td class=\"spacer-lg\"></td>\n" + " </tr>\n" + " <tr>\n" + " <td class=\"panel-body\">\n" + " <table border=\"0\" cellpadding=\"0\" cellspacing=\"0\" role=\"presentation\" width=\"100%\">\n" + " <tbody><!-- Start Text -->\n" + " <tr>\n" + " <td align=\"left\" class=\"headline-one text-dark-gray\">Your Monthly Email statistics for {{MonthName}}</td>\n" + " </tr>\n" + " <tr>\n" + " <td class=\"spacer-md\"></td>\n" + " </tr> \n" + " <tr>\n" + " <td align=\"left\" class=\"headline-two text-dark-gray\">You sent {{EmailCount}} Email<p></td>\n" + " </tr>\n" + " <tr>\n" + " <td><img src='{{SmsSentDailyCharUrl}}' /></td>\n" + " </tr>\n" + " <tr>\n" + " <td class=\"spacer-sm\"></td>\n" + " </tr>\n" + " <tr>\n" + " <td align=\"left\" class=\"headline-two text-dark-gray\">Your delivery rate: {{deliveryRate}}</td>\n" + " </tr>\n" + " <tr>\n" + " <td><img src='{{deliveryRateCharUrl}}' /></td>\n" + " </tr>\n" + " <tr>\n" + " <td class=\"spacer-sm\"></td>\n" + " </tr>\n" + " <tr>\n" + " <td class=\"spacer-md\"></td>\n" + " </tr> \n" + " <tr>\n" + " <td class=\"spacer-md\"></td>\n" + " </tr> \n" + " <!-- Start Text -->\n" + " <tr>\n" + " <td class=\"spacer-sm\"></td>\n" + " </tr> \n" + " <tr>\n" + " <td align=\"left\" class=\"body text-dark-gray\">If you have any questions or comments please contact technical support at&nbsp;<a class=\"body text-primary\" href=\"tel:1-866-848-8282\">1-866-848-8282</a>.</td>\n" + " </tr>\n" + " <!-- End Text -->\n" + " <tr>\n" + " <td class=\"spacer-lg\"></td>\n" + " </tr>\n" + " <!-- Start Text -->\n" + " <tr>\n" + " <td align=\"left\" class=\"body text-dark-gray\">GEM-CAR,<br />\n" + " Automated system</td>\n" + " </tr>\n" + " <tr>\n" + " <td class=\"spacer-md\"></td>\n" + " </tr> \n" + " <tr>\n" + " <td align=\"left\" class=\"body text-dark-gray\">\n" + " This message was sent from an unmonitored address. Please do not respond to this message.\n" + " </td>\n" + " </tr>\n" + " <!-- End Text -->\n" + " </tbody>\n" + " </table>\n" + " </td>\n" + " </tr>\n" + " <tr>\n" + " <td class=\"spacer-lg\"></td>\n" + " </tr>\n" + " </tbody>\n" + " </table>\n" + " <!-- End Panel Container --></td>\n" + " </tr>\n" + " <tr>\n" + " <td class=\"spacer-lg\"></td>\n" + " </tr>\n" + " <!-- Start Footer -->\n" + " <tr>\n" + " <td align=\"left\" id=\"footer\">\n" + " <table border=\"0\" cellpadding=\"0\" cellspacing=\"0\" role=\"presentation\">\n" + " <tbody>\n" + " <tr>\n" + " <td align=\"left\">\n" + " <table border=\"0\" cellpadding=\"0\" cellspacing=\"0\" role=\"presentation\">\n" + " <tbody>\n" + " <tr>\n" + " <td valign=\"top\" width=\"28\"><a href=\"https://www.facebook.com/GEMCARSOFTWARE\"><img alt=\"Icon\" border=\"0\" src=\"https://data.gem-support.com/s/9N2ZwefogzzJCEP/preview\" width=\"32\" /> </a></td>\n" + " <td width=\"16\"></td>\n" + " <td valign=\"top\" width=\"28\"><a href=\"https://twitter.com/GEMCARSOFTWARE\"><img alt=\"Icon\" border=\"0\" src=\"https://data.gem-support.com/s/4RX8koXXJp5EPHq/preview\" width=\"32\" /> </a></td>\n" + " <td width=\"16\"></td>\n" + " <td valign=\"top\" width=\"28\"><a href=\"https://ca.linkedin.com/pub/mathieu-brunel/3/678/466/\"><img alt=\"Icon\" border=\"0\" src=\"https://data.gem-support.com/s/zgScwGzsnTojya6/preview\" width=\"32\" /> </a></td>\n" + " <td width=\"16\"></td>\n" + " <td valign=\"top\" width=\"28\"><a href=\"https://www.youtube.com/user/RepairShopSoftware/\"><img alt=\"Icon\" border=\"0\" src=\"https://data.gem-support.com/s/66SSwNQy2RKYmt8/preview\" width=\"32\" /> </a></td>\n" + " </tr>\n" + " </tbody>\n" + " </table>\n" + " </td>\n" + " </tr>\n" + " <tr>\n" + " <td class=\"spacer-sm\"></td>\n" + " </tr>\n" + " <tr>\n" + " <td align=\"left\" class=\"body text-secondary\">&bull; V2V Technologies Inc. All rights reserved.<br />\n" + " <span class=\"address\">4460 rue B&eacute;langer, Montr&eacute;al, Qc H1T 1B5</span></td>\n" + " </tr>\n" + " <tr>\n" + " <td class=\"spacer-md\"></td>\n" + " </tr>\n" + " <tr>\n" + " <td align=\"left\" class=\"body text-secondary\">You are receiving this email because you are a GEM-CAR customer.<br />\n" + " <a class=\"body text-primary\" href=\"https://www.gem-car.com\">Visite us</a> | <a class=\"body text-primary\" href=\"https://www.gem-car.com/faqs/\">Support FAQ</a> | <a class=\"body text-primary\" href=\"{{unsubscribeURL}}\">Unsubscribe</a></td>\n" + " </tr>\n" + " </tbody>\n" + " </table>\n" + " </td>\n" + " </tr>\n" + " <!-- End Footer -->\n" + " <tr>\n" + " <td class=\"spacer-lg\"></td>\n" + " </tr>\n" + " </tbody>\n" + "</table>\n" + "<!-- End Email Container --></center>\n" + "</body>\n" + "</html>"; final Pattern pattern = Pattern.compile(regex); 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