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

/
/
gmi

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 = "(?:\"?[a-z0-9_\\-]{0,256}(?:key|secret|token)[a-z0-9_\\-]{0,256}\"?\\s{0,10}(?::|=)\\s{0,10}\\\"?(?!null|true|false)([a-z0-9+_:\\.\\-\\/]{1,1024})|\"Authorization\":\"[a-z0-9+:_\\-\\/]{1,1024}\\s(.{1,1024}?(?<!\\\\)(?=\")))"; final String string = "{\"secret\":\"asdfffasdf\",\"headers\":{\"uri_1\":\"https://www.api.example.com/api/?count=433&apiKey=DD238B9E4369248330EFBB58D6B1431AFB03C8E1D&debug=true\",\"uri_2\":\"https://www.api.example.com/api/?secret=5ZQD9jhp51qVE5199xU4zj2X2wSPGwNpDub2CiSJO3i\",\"uri_3\":\"https://www.api.example.com/api/?token=CE362359AAFCB1F8C5BAF4692FD67C18&debug=true\",\"uri_4\":\"https://www.api.example.com/api/?secret_token=4DA9155E26A75C6D83E208FF518EAFE4&debug=true\",\"uri_5\":\"https://www.api.example.com/api/?count=433&key=NeRPfka6TETPfHvNoLP4WPBxhhsrOzOh9HyC&debug=true\",\"uri_6\":\"https://www.api.example.com/api/?apitoken=jq3PGKQDhKjJVo33hRVPK36q0r9-asdf_asdf\",\"uri_7\":\"https://www.api.example.com/api/?api_key=7119971F47DE25C366F9AB506A1BFD&debug=true\",\"uri_8\":\"https://www.api.example.com/api/?secret-key=93326A9B41C3DF94BED6E4C9DC524A4F6\",\"uri_9\":\"https://www.api.example.com/api/?client_secret=6C844DE60C4104936541D4EAB32404DA&debug=true\",\"uri_10\":\"https://www.api.example.com/api/?count=433&list=daisy&test=true&api_token=lYb6y4GYvFjmW0F8bGAXtcogmkRGa3hkgph530&debug=true\",\"uri_11\":\"https://www.api.example.com/api/?count=433&api_secret=lYb6y4GYvFjmW0F8bGAXtcogmkRGa3hkgph530&debug=true\",\"uri_12\":\"https://www.api.example.com/api/?token-pin=8433\",\"uri_13\":\"https://www.api.example.com/api/?key=4343\",\"uri_14\":\"https://www.api.example.com/api/?secret-pin=32211190332933\",\"auth_0\":{\"Authorization\":\"Digest username=username, asfsfsf=\\\"dsffadf\\\",\\nasfsfsf=\\\"dsffadf\\\",\\nasfsfsf=\\\"dsffadf\\\",\\nasdfsf=asdfsdf\"},\"auth_1\":{\"Authorization\":\"Bearer dasd/4rV4MjOdjA3pu9rJ5qc9RKuCoAO8UaxuWUGXUtuzRJKdRTvKMVe3dJ9FN1SyF9n==\"},\"auth_2\":{\"Authorization\":\"App D4D0BB1B2F12B5E97405C764CA45F\"},\"auth_3\":{\"Authorization\":\"IPSO dasd+F51B63334AD3520894712D15D8F1105ED3DD\"},\"auth_4\":{\"Authorization\":\"Key hJdilwrzM9616MJsDGBiK4qjeJFYB0zmHPxYNUrn8D54ycAN7gwedqHt0UiCWTb\"},\"auth_5\":{\"Authorization\":\"Digest username=username, oauth=\\\"hhasjjjd+ddad\\\",\\nnonce=\\\"dsffadf\\\",\\nhash=\\\"ef05bc-89c2\\\",\\nclient=myapp\"},\"auth_6\":{\"Authorization\":\"Digest username=\\\"6551156d‑569c‑4b7d‑945f‑310ff10943c5\\\", realm=\\\"bob@contoso.com\\\", qop=auth, algorithm=MD5-sess, uri=\\\"sip:bob@contoso.com;gruu;opaque=app:conf:focus:id:854T0R7G\\\", nonce=\\\"h8A4ZW22ygGZozIIGZcb43waVMEM6Gq\\\", nc=1, cnonce=\\\"\\\", opaque=\\\"0C1D4536\\\", response=\\\"b4543cd4d6a923b4ab4fd4583af48f0e\\\"\"},\"auth_7\":{\"Authorization\":\"Digest username=\\\"6551156d‑569c‑4b7d‑945f‑310ff10943c5\\\",\\n realm=\\\"bob@contoso.com\\\",\\n qop=auth,\\n algorithm=MD5-sess,\\n uri=\\\"sip:bob@contoso.com;gruu;opaque=app:conf:focus:id:854T0R7G\\\",\\n nonce=\\\"h8A4ZW22ygGZozIIGZcb43waVMEM6Gq\\\",\\n nc=1, cnonce=\\\"\\\",\\n opaque=\\\"0C1D4536\\\",\\n response=\\\"b4543cd4d6a923b4ab4fd4583af48f0e\\\"\"},\"apiId\":null,\"apiId_2\":null,\"apiKey4\":12345689994,\"apiKey5\":\"123344555\",apiKey\":null,\"apiKey2\":null,\"apiKey3\":\"null\"},\"multiValueHeaders\":{\"Accept\":[\"*/*\"],\"Accept-Encoding\":[\"gzip, deflate, br\"],\"Cache-Control\":[\"no-cache\"],\"Host\":[\"myapi.api.example.com\"],\"Postman-Token\":[\"86071fc6-35da-4ff5-8eb5-d44ce06e3eed\"],\"User-Agent\":[\"PostmanRuntime/7.31.1\"],\"X-Amzn-Trace-Id\":[\"Root=1-6428887b-15fa842f16c1eeaf5d812345\"],\"X-Forwarded-For\":[\"10.61.41.39\"],\"X-Forwarded-Port\":[\"443\"],\"X-Forwarded-Proto\":[\"https\"],\"Client-Secret\":[\"451234567890123456\",\"90123456789012345\",\"e3bc8a2051bae92cc32\",8123456789012345678,\"ed1234567890ca1234\"],\"Client-Token\":[\"awbu+d4Tey28-32ntRW3X\",82340514553298753123456,\"hw_538291-ec0a91-123456\"]}}\n"; final Pattern pattern = Pattern.compile(regex, Pattern.MULTILINE | Pattern.CASE_INSENSITIVE); 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