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

r"
"

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 = "(\\{(?:.|\\n)*\\})"; final String string = "// API callback\n" + "google.search.Search.apiary2387({\n" + " \"cursor\": {\n" + " \"currentPageIndex\": 0,\n" + " \"estimatedResultCount\": \"4490\",\n" + " \"moreResultsUrl\": \"http://www.google.com/cse?oe=utf8&ie=utf8&source=uds&q=ssh&start=0&sort=&cx=013305635491195529773:0ufpuq-fpt0\",\n" + " \"resultCount\": \"4,490\",\n" + " \"searchResultTime\": \"0.22\",\n" + " \"pages\": [\n" + " {\n" + " \"label\": 1,\n" + " \"start\": \"0\"\n" + " },\n" + " {\n" + " \"label\": 2,\n" + " \"start\": \"1\"\n" + " },\n" + " {\n" + " \"label\": 3,\n" + " \"start\": \"2\"\n" + " },\n" + " {\n" + " \"label\": 4,\n" + " \"start\": \"3\"\n" + " },\n" + " {\n" + " \"label\": 5,\n" + " \"start\": \"4\"\n" + " },\n" + " {\n" + " \"label\": 6,\n" + " \"start\": \"5\"\n" + " },\n" + " {\n" + " \"label\": 7,\n" + " \"start\": \"6\"\n" + " },\n" + " {\n" + " \"label\": 8,\n" + " \"start\": \"7\"\n" + " },\n" + " {\n" + " \"label\": 9,\n" + " \"start\": \"8\"\n" + " },\n" + " {\n" + " \"label\": 10,\n" + " \"start\": \"9\"\n" + " }\n" + " ]\n" + " },\n" + " \"context\": {\n" + " \"title\": \"Pastebin Active\",\n" + " \"total_results\": \"0\",\n" + " \"facets\": []\n" + " },\n" + " \"results\": [\n" + " {\n" + " \"GsearchResultClass\": \"GwebSearch\",\n" + " \"cacheUrl\": \"http://www.google.com/search?q=cache:PBL2A25kpZoJ:pastebin.com\",\n" + " \"clicktrackUrl\": \"https://www.google.com/url?q=http://pastebin.com/u/ssh&sa=U&ved=0ahUKEwiO4fjNpovMAhWBPxoKHYJXAS4QFggEMAA&client=internal-uds-cse&usg=AFQjCNHczEhDXdcUnRZhpArEeSiHfjwMJA\",\n" + " \"content\": \"BitBucket - Backup your code in the cloud! Host unlimited private projects, for free\\n. SIGN UP takes 10 seconds, and it&#39;s free! Guest&nbsp;...\",\n" + " \"contentNoFormatting\": \"BitBucket - Backup your code in the cloud! Host unlimited private projects, for free\\n. SIGN UP takes 10 seconds, and it's free! Guest ...\",\n" + " \"formattedUrl\": \"pastebin.com/u/\\u003cb\\u003essh\\u003c/b\\u003e\",\n" + " \"title\": \"\\u003cb\\u003eSsh&#39;s\\u003c/b\\u003e Pastebin - Pastebin.com\",\n" + " \"titleNoFormatting\": \"Ssh's Pastebin - Pastebin.com\",\n" + " \"unescapedUrl\": \"http://pastebin.com/u/ssh\",\n" + " \"url\": \"http://pastebin.com/u/ssh\",\n" + " \"visibleUrl\": \"pastebin.com\",\n" + " \"richSnippet\": {\n" + " \"cseImage\": {\n" + " \"src\": \"http://pastebin.com/i/facebook.png\"\n" + " },\n" + " \"metatags\": {\n" + " \"fbAppId\": \"231493360234820\",\n" + " \"ogTitle\": \"Ssh's Pastebin - Pastebin.com\",\n" + " \"ogType\": \"article\",\n" + " \"ogUrl\": \"http://pastebin.com/u/ssh\",\n" + " \"ogImage\": \"http://pastebin.com/i/facebook.png\",\n" + " \"ogSiteName\": \"Pastebin\",\n" + " \"viewport\": \"width=device-width, maximum-scale=1.0, user-scalable=no\"\n" + " }\n" + " }\n" + " }\n" + " ]\n" + "}\n" + ");"; final Pattern pattern = Pattern.compile(regex); final Matcher matcher = pattern.matcher(string); if (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