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
Processing...

Test String

Code Generator

Language

Generated Code

import re regex = re.compile(r"<link rel=\"canonical\" href=\"(.*?)\">", flags=re.MULTILINE) test_str = ("const regex = /\"sku\": \"(.*?)\"/gm;\n\n" "// Alternative syntax using RegExp constructor\n" "// const regex = new RegExp('\"sku\": \"(.*?)\"', 'gm')\n\n" "const str = ``<!DOCTYPE html>\n" "<!-- saved from url=(0044)https://www.daz3d.com/karmen-9-hd-pro-bundle -->\n" "<html xmlns=\"http://www.w3.org/1999/xhtml\" xml:lang=\"en\" lang=\"en\" class=\"\"><head><meta http-equiv=\"Content-Type\" content=\"text/html; charset=UTF-8\">\n\n" "<title>Karmen 9 HD Pro Bundle | Daz 3D</title>\n" "<meta name=\"viewport\" content=\"width=device-width, initial-scale=1\">\n" "<meta name=\"description\" content=\"&lt;p&gt;Introducing the Karmen 9 HD Pro Bundle. This all-inclusive bundle features a vibrant makeup look, expressions, a curly and braided bun hairstyle, apocalyptic-inspired outfits, Elemental Mage and Shadow Realm attire, and even monstrous poses to immerse \">\n" "<meta name=\"keywords\" content=\"Karmen 9 HD Pro Bundle\">\n" "<meta http-equiv=\"X-UA-Compatible\" content=\"IE=edge\">\n" "<meta name=\"robots\" content=\"INDEX,FOLLOW,noai, noimageai\">\n" "<link rel=\"icon\" href=\"https://www.daz3d.com/static/images/favicon.ico\" type=\"image/x-icon\">\n" "<link rel=\"shortcut icon\" href=\"https://www.daz3d.com/static/images/favicon.ico\" type=\"image/x-icon\">\n" "<!--[if lt IE 7]>\n" "<script type=\"text/javascript\">\n" "//<![CDATA[\n" " var BLANK_URL = '/js/blank.html';\n" " var BLANK_IMG = '/js/spacer.gif';\n" "//]]>\n" "</script>\n" "<![endif]-->\n" "<link rel=\"stylesheet\" href=\"./Karmen 9 HD Pro Bundle _ Daz 3D_files/design-533ce80c63b6085aedc802b14d1faa79.css\" about=\"0\">\n" "<link rel=\"stylesheet\" href=\"./Karmen 9 HD Pro Bundle _ Daz 3D_files/product_zoom-5de5dd875434871413473d85f684dcfc.css\" about=\"1\">\n" "<style>\n" " @keyframes spinner {\n" " 0% {\n" " transform: translateY(-50%) rotate(0deg);\n" " }\n\n" " 100% {\n" " transform: translateY(-50%) rotate(360deg);\n" " }\n" " }\n\n" " .spinner::after {\n" " animation: 1.5s linear infinite spinner;\n" " animation-play-state: inherit;\n" " border: solid 3px #cfd0d1;\n" " border-bottom-color: #1c87c9;\n" " border-radius: 50%;\n" " content: \"\";\n" " height: 20px;\n" " width: 20px;\n" " display: inline-flex;\n" " flex-direction: column;\n" " padding-bottom: 5px;\n" " }\n" " </style>\n" "<script src=\"./Karmen 9 HD Pro Bundle _ Daz 3D_files/getIds\" type=\"text/javascript\" async=\"\"></script><script type=\"text/javascript\" id=\"www-widgetapi-script\" src=\"./Karmen 9 HD Pro Bundle _ Daz 3D_files/www-widgetapi.js.download\" async=\"\"></script><script async=\"\" src=\"./Karmen 9 HD Pro Bundle _ Daz 3D_files/fbevents.js.download\"></script><script type=\"text/javascript\" async=\"\" src=\"./Karmen 9 HD Pro Bundle _ Daz 3D_files/bat.js.download\"></script><script type=\"text/javascript\" async=\"\" src=\"./Karmen 9 HD Pro Bundle _ Daz 3D_files/pixel.js.download\"></script><script type=\"text/javascript\" async=\"\" src=\"./Karmen 9 HD Pro Bundle _ Daz 3D_files/analytics.js.download\"></script><script type=\"text/javascript\" async=\"\" src=\"./Karmen 9 HD Pro Bundle _ Daz 3D_files/js\"></script><script type=\"text/javascript\" async=\"\" src=\"./Karmen 9 HD Pro Bundle _ Daz 3D_files/destination\"></script><script src=\"./Karmen 9 HD Pro Bundle _ Daz 3D_files/tag.js.download\" type=\"text/javascript\" async=\"\" id=\"cjapitag\"></script><script async=\"\" src=\"./Karmen 9 HD Pro Bundle _ Daz 3D_files/affirm.js.download\"></script><script type=\"text/javascript\" async=\"\" src=\"./Karmen 9 HD Pro Bundle _ Daz 3D_files/0\"></script><script src=\"./Karmen 9 HD Pro Bundle _ Daz 3D_files/core-ed1ca31447e4f2e9bbf6d9ef38afe3c6.js.download\"></script>\n" "<style>\n" " @keyframes spinner {\n" " 0% {\n" " transform: translateY(-50%) rotate(0deg);\n" " }\n\n" " 100% {\n" " transform: translateY(-50%) rotate(360deg);\n" " }\n" " }\n\n" " .spinner::after {\n" " animation: 1.5s linear infinite spinner;\n" " animation-play-state: inherit;\n" " border: solid 3px #cfd0d1;\n" " border-bottom-color: #1c87c9;\n" " border-radius: 50%;\n" " content: \"\";\n" " height: 20px;\n" " width: 20px;\n" " display: inline-flex;\n" " flex-direction: column;\n" " padding-bottom: 5px;\n" " }\n" " </style>\n" "<script src=\"./Karmen 9 HD Pro Bundle _ Daz 3D_files/zoom-fee76dde1f2c855960b29036b231c115.js.download\"></script>\n" "<script type=\"application/ld+json\">{\n" " \"brand\": {\n" " \"name\": \"Daz 3D\",\n" " \"@type\": \"Brand\"\n" " },\n" " \"@context\": \"https://schema.org/\",\n" " \"description\": \"Introducing the Karmen 9 HD Pro Bundle. This all-inclusive bundle features a vibrant makeup look, expressions, a curly and braided bun hairstyle, apocalyptic-inspired outfits, Elemental Mage and Shadow Realm attire, and even monstrous poses to immerse your character into any narrative from modern desert to fantasy to horror.\",\n" " \"image\": \"https://gcdn.daz3d.com/p/91909/i/shimuzu_Karmen_Pro_Bundle.jpg\",\n" " \"name\": \"Karmen 9 HD Pro Bundle\",\n" " \"offers\": {\n" " \"availability\": \"https://schema.org/InStock\",\n" " \"itemCondition\": \"https://schema.org/NewCondition\",\n" " \"price\": 185.99,\n" " \"priceCurrency\": \"USD\",\n" " \"@type\": \"Offer\"\n" " },\n" " \"sku\": \"91909\",\n" " \"@type\": \"Product\"\n" "}</script>\n" "<link rel=\"canonical\" href=\"https://www.daz3d.com/karmen-9-hd-pro-bundle\">\n" "<script>\n" " if (!daz) { var daz = {}; };\n" " daz.api = new DazApi()\n\n" " from 331.2deg,\n" " var(--border-color-1),\n" " var(--border-color-2),\n" " var(--border-color-1),\n" " var(--border-color-2),\n" " var(--border-color-1)\n" " )\n" " 1;\n" " }\n" " 93% {\n" " border-image: conic-gradient(\n" " from 334.8deg,\n" " var(--border-color-1),\n" " var(--border-color-2),\n" " var(--border-color-1),\n" " var(--border-color-2),\n" " var(--border-color-1)\n" " )\n" " 1;\n" " }\n" " 94% {\n" " border-image: conic-gradient(\n" " from 338.4deg,\n" " var(--border-color-1),\n" " var(--border-color-2),\n" " var(--border-color-1),\n" " var(--border-color-2),\n" " var(--border-color-1)\n" " )\n" " 1;\n" " }\n" " 95% {\n" " border-image: conic-gradient(\n" " from 342deg,\n" " var(--border-color-1),\n" " var(--border-color-2),\n" " var(--border-color-1),\n" " var(--border-color-2),\n" " var(--border-color-1)\n" " )\n" " 1;\n" " }\n" " 96% {\n" " border-image: conic-gradient(\n" " from 345.6deg,\n" " var(--border-color-1),\n" " var(--border-color-2),\n" " var(--border-color-1),\n" " var(--border-color-2),\n" " var(--border-color-1)\n" " )\n" " 1;\n" " }\n" " 97% {\n" " border-image: conic-gradient(\n" " from 349.2deg,\n" " var(--border-color-1),\n" " var(--border-color-2),\n" " var(--border-color-1),\n" " var(--border-color-2),\n" " var(--border-color-1)\n" " )\n" " 1;\n" " }\n" " 98% {\n" " border-image: conic-gradient(\n" " from 352.8deg,\n" " var(--border-color-1),\n" " var(--border-color-2),\n" " var(--border-color-1),\n" " var(--border-color-2),\n" " var(--border-color-1)\n" " )\n" " 1;\n" " }\n" " 99% {\n" " border-image: conic-gradient(\n" " from 356.4deg,\n" " var(--border-color-1),\n" " var(--border-color-2),\n" " var(--border-color-1),\n" " var(--border-color-2),\n" " var(--border-color-1)\n" " )\n" " 1;\n" " }\n" " 100% {\n" " border-image: conic-gradient(\n" " from 360deg,\n" " var(--border-color-1),\n" " var(--border-color-2),\n" " var(--border-color-1),\n" " var(--border-color-2),\n" " var(--border-color-1)\n" " )\n" " 1;\n" " }\n" " }\n" " }\n\n" " /* END rotate bonus box border */\n" " /* BEGIN falling stars animation */\n\n" " .bg-stars {\n" " width: 100%;\n" " height: 100%;\n" " position: absolute;\n" " top: 0;\n" " left: 0;\n" " overflow: hidden;\n" " }\n\n" " .bg-stars .bg-star {\n" " font-size: 1em;\n" " position: absolute;\n" " top: -25px;\n" " color: yellow;\n" " user-select: none;\n" " cursor: default;\n" " text-shadow: 0 0 1px #000;\n" " animation-name: fallingStars;\n" " animation-duration: 5s;\n" " animation-timing-function: linear;\n" " animation-iteration-count: infinite;\n" " animation-play-state: running;\n" " z-index: -1;\n" " }\n" " \n" " .bg-stars .bg-star:nth-of-type(1) {\n" " left: 10%;\n" " -webkit-animation-delay: 1s, 1s;\n" " animation-delay: 1s, 1s;\n" " }\n\n" " .bg-stars .bg-star:nth-of-type(2) {\n" " left: 20%;\n\n\n" "</div></body></html>(`;\n" "let m;\n\n" "while ((m = regex.exec(str)) !== null) {\n" " // This is necessary to avoid infinite loops with zero-width matches\n" " if (m.index === regex.lastIndex) {\n" " regex.lastIndex++;\n" " }\n" " // The result can be accessed through the `m`-variable.\n" " m.forEach((match, groupIndex) => {\n" " console.log(`Found match, group ${groupIndex}: ${match}`);\n" " });\n" "}\n") matches = regex.finditer(test_str) for match_num, match in enumerate(matches, start=1): print(f"Match {match_num} was found at {match.start()}-{match.end()}: {match.group()}") for group_num, group in enumerate(match.groups(), start=1): print(f"Group {group_num} found at {match.start(group_num)}-{match.end(group_num)}: {group}")

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