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

/
/
gmysi

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 = "([\\-]*BEGIN\\sCERTIFICATE\\sREQUEST[\\-]+.+[-]+END\\sCERTIFICATE\\sREQUEST[-]+)"; final String string = "-----BEGIN CERTIFICATE REQUEST-----\n" + "MIIEuDCCAqACAQAwczELMAkGA1UEBhMCVVMxGDAWBgNVBAMMD3BsdWdpYmlsaXR5\n" + "LmNvbTEXMBUGA1UEBwwOU2FsdCBMYWtlIENpdHkxFDASBgNVBAoMC1BsdWdpYmls\n" + "aXR5MQ0wCwYDVQQIDARVdGFoMQwwCgYDVQQLDANPcmcwggIiMA0GCSqGSIb3DQEB\n" + "AQUAA4ICDwAwggIKAoICAQCfQqx8YexJ4HjGqIpywxvTOPDnqIaZicD3IQSUdAb5\n" + "5vcfAaD/0KBH/6Oa2NPlq4mYAw2octDiuklvkXIUgnn85vwlj6fLm6iR6i1tjM3g\n" + "tusxur3fmMdF9YqDNNM7LVSxXMq/vXuChPj3bVib2EyKJRcBn8EMTnJYdfl3YK4l\n" + "j+KW7cnxIy8E3DAy4KIUPbI2LNPix43emW6XuMB3hpvcbs2YpQogagAQwvNYAIcW\n" + "Ub3+fSEbXFNVmYFRPbd7T5Arei4Ubl8kKVWfqUnWIOdYQh7o0CbQl+67ivAyRnDU\n" + "oItNtPz+seWzL1xerjQqdlHrCQFGNfLdI3Hfl9SZVKOqdsjs2bEiP+C6E/pilvu/\n" + "zEtD5VbGd0UBBZtANm6BdBEhhigX8vL/FfiqxlPsEK31L9tQnwa6ETvcVbRQoXBW\n" + "idJJKCmiScz17ML8aTxw0zXc16CBHuE4AEV7xaNmdl5NsYCB+q/H3SCVsreMnu7A\n" + "cpCgvaCZX1/8zSWrVNMf0i+/gJCoBh1OXNnqtCPycJDPvrVGYF2U7RqzC4c91Kqe\n" + "QxEKHApEJAL47nFtM9c3K2fNvLEVOD+k+iDkEuL++VHaXO3VHCiVoJjQCSNTChl3\n" + "aSL29LadjcPvf2QdMymEJ4+wKI8u6l1bk51zN0INnVDDkMdtfCu0C8ux8M4roP9Y\n" + "kQIDAQABoAAwDQYJKoZIhvcNAQELBQADggIBAJO3HIp2hvkQh6/Bk19RiEdyfJjb\n" + "xoPWtfM4lWDyXLxq6HrmKadvOtjTs9fGpoBRJaknIhy8n0/oN8Et+uFgga3ptb/8\n" + "AjyDRVqmYK3byAJrUm055v9VseNwFqE/hsZiFtPMVA5I5agtnQm8o6zPgUSMQWso\n" + "evA00Fa+Q1X1Hmbthtd2ZH64cxLOqW3vW9LViBp9C52mU1NyZtvPRJAlcOlH1r9A\n" + "MFnPrR7T4HJ8gMEvaj0likFr5nQKWH5ScPvHbIKyIoebn9RznbMZBNjUn60+I0Kt\n" + "VwN8UrIwZMNF+eL99I6kEr/gjoZ3VegPH7YaVRQ280L4NvZNKMbAr1Z+uyCD587y\n" + "Zf+cbzZB30xTfra0/iUQnGEBuScpGQMdXEzmE/lBCnNnqnNohrAwvQNLISbnK7w2\n" + "JUrwbIIgRrLmmXGELPQ7vBkKmCtSrmPGLyWctwG005h8hHLtFk8jagSDJ/gTQ3Wv\n" + "n7YEy3ROHujz/UVGrGE2P3oKs5prn+N52HIxM9XoaQndrtbyvkaOe+WHGZ0htQkE\n" + "H6Rrh0YijAFpZTsKwv1ndMh2HpoaYX3B1s9ky3TWGAdOMCgHgdBFpvk2+PdDN+6a\n" + "Js+0VtfRywLxxaEamLciBj6JmjybIEBSANSwf2pdn8OnMq5BLZrLRWhsaMVGlciL\n" + "1JPHcsgLz1lD8FYC\n" + "-----END CERTIFICATE REQUEST-----\n\n" + "-----BEGIN PRIVATE KEY-----\n" + "MIIJQgIBADANBgkqhkiG9w0BAQEFAASCCSwwggkoAgEAAoICAQCfQqx8YexJ4HjG\n" + "qIpywxvTOPDnqIaZicD3IQSUdAb55vcfAaD/0KBH/6Oa2NPlq4mYAw2octDiuklv\n" + "kXIUgnn85vwlj6fLm6iR6i1tjM3gtusxur3fmMdF9YqDNNM7LVSxXMq/vXuChPj3\n" + "bVib2EyKJRcBn8EMTnJYdfl3YK4lj+KW7cnxIy8E3DAy4KIUPbI2LNPix43emW6X\n" + "uMB3hpvcbs2YpQogagAQwvNYAIcWUb3+fSEbXFNVmYFRPbd7T5Arei4Ubl8kKVWf\n" + "qUnWIOdYQh7o0CbQl+67ivAyRnDUoItNtPz+seWzL1xerjQqdlHrCQFGNfLdI3Hf\n" + "l9SZVKOqdsjs2bEiP+C6E/pilvu/zEtD5VbGd0UBBZtANm6BdBEhhigX8vL/Ffiq\n" + "xlPsEK31L9tQnwa6ETvcVbRQoXBWidJJKCmiScz17ML8aTxw0zXc16CBHuE4AEV7\n" + "xaNmdl5NsYCB+q/H3SCVsreMnu7AcpCgvaCZX1/8zSWrVNMf0i+/gJCoBh1OXNnq\n" + "tCPycJDPvrVGYF2U7RqzC4c91KqeQxEKHApEJAL47nFtM9c3K2fNvLEVOD+k+iDk\n" + "EuL++VHaXO3VHCiVoJjQCSNTChl3aSL29LadjcPvf2QdMymEJ4+wKI8u6l1bk51z\n" + "N0INnVDDkMdtfCu0C8ux8M4roP9YkQIDAQABAoICAGRnX2DnR1Vn/ByaQvaJBPDM\n" + "NCyINZt0mj/zA/UnlQJV1zQoDb1ZZMMfaqCD1Es2Mv+v5RtujzxxXzzEQFynyYpk\n" + "gVCY2Ztmngan0U4AeAcUqwBmD7B4nCEB5PpFAmqLcJqEupnZNpWZiXBL8pIF8nMh\n" + "YPi4I7fDeRlF/ymAvSmXJa4raaXpnYn92zEoJ2aFYuX+qvKNBmbw6iUi58wzA+4b\n" + "uOhkHBdFXJc0oL+5TXEHxbU8Y/Pg5/TOWxXBx/wos+aFF6nvz3F30bBfxNoHUnJ0\n" + "9RGnsODO+EYqGLZJbHbQZCJwWROlSgAGesCCKQcgIxL/UVtXRa6e2vqwuOqVzrv5\n" + "msBFM/HzcUvdtNq4FP2UfcqAi4FZlwHlbTDphE3fZSPbLIoJZLuhKuJPFA/Sc8L/\n" + "ABPnmRqb0bZ2RKECBnXrsV0U/KeSxbY4r0Hj+ggBnLNO1VhlYjCQZlCXA4X8LdyV\n" + "wBvoNeKjSo3ZD8vr/Jvpdm/9xiWVikbPqYpiEiIn6iN8omYWjxHWgDox9fd+zVQu\n" + "c/3giKEVAQYhNYj+YbkZpmnWQNjdL89TatjdBeaWO9Zq4k1VwN5UYB539O61kHfC\n" + "bhpYx/ptIgTBdEwp+ohlkAegCyBS+Mo3SiQocATdpeBwAMoMpMOtCiMDyGjydK0Y\n" + "2xi5+uOGMDKMbWvRe10FAoIBAQDMnaqknzt8Brc1KHQVv7Ww0VTrCEjItXLaAIOs\n" + "AW9PyL6/9lhFYljCnEGcWL3LAZlhldr81aNE40qw5FVVRrTR2Hg3xF/znZwa6Bnc\n" + "0t1XXGRj0BZIH5OrZSdf0gXdEwIrIB2LmllxMMpzd0BSgX/+x6k2K6FMAl/048bg\n" + "v986GsRwUjrlkt0ihyQNHlWuKKK82W1G6G4iQiC0bD5i/AUBer9o5Yb4X9GrgoIA\n" + "nWJIHstfJ80KTOJMQVczj0SKLmTjnIUE91BcXGhqTTdcSKTWbts50HyuwQAYcZco\n" + "vW5B5Sbyf57jCvu68Bo3gxngE1xYjtTR6Q13azII4DxyE7MjAoIBAQDHQTMNW8NQ\n" + "unvr64yqCwzBmEmpCJ6NEbYub3rqHzQPe5Na5VN1iTujKx5ifhi5uhR5A5Jluy2O\n" + "fUWzF/ihEdVOOh0JPj1NiJkY1VkuiY9Y2aHR2+8st06sp92Zj1i7Us/t+CP+WuOv\n" + "m7He4xRRrXx9tXcdpAzaTr8NoKXCL1fz4t8HKUZdfvvCtY+Ghd3ct1rEG8Bi9SUF\n" + "yBoTE1NwATHLCsYFURhpmWwnQTMpRTjlhogNSywDG59fdcqyEBUacCnPG7ZxZ3c2\n" + "N8VWknZsf9hBEyjyGCvTNq1A0KKJ6PIEp2gOoMi4I1nbKB1jSC7Gh61pJ+aV4L6g\n" + "M10Jh890RWq7AoIBAQC8vvv4G0Jd6Dv79zMOFOffEVpJ7DxnmKk3W54afsBVUpJS\n" + "tUU7y7qg2k7TkDCTIQiBsiBtdgzDsP7nKdllbnHB2PMcTjNMoCit0Uh6ILE4suuP\n" + "/xVutmIbipXFmBD8m1o2uctHSbwT47P8yxY0hWyycy8t3xVM7ivh1HNSQuwBx0tJ\n" + "aTEXMGB4Rz0ENOVIYAeuOMrKzAE77NAKXoc1+9AKS1Zhxsi4OHtKwHp3YraUXIOx\n" + "ZR+Izt85BFUSJKhO5vj91RYHPLOOX1eaJ1xX7lLP0za6oA1Djpkt8ypC1Grushk5\n" + "PGwud6U6Dd3BM1gdEP7wWeELOPXJIMLo2SApAu8NAoIBAGjYmPl9gJ/ZEN4KOyE6\n" + "4UJ5VME6RNusJzX1+TJ6qtU+zEH3C9x8EsKALOPcwDvye1VWGNGpFYa1ylg709tF\n" + "W/1mvOKhOnay2wRjNyMyxRgWpHyeAxN/fUmCpytnb2RaZgktGht8TfSYs5a53HZC\n" + "GJC5TO1u5kh1STjtgGtWqCwwA/VrtZf6+pTxHo3FoQHEBWHNzIUFw65wJbBF6hC0\n" + "wDO7/ojLrFHcpjldqIMd5pt4F90O4iDchxcfD0J1DfW0cXuGdJDlxafk3tT4CpJ7\n" + "Dxrm7xO8vkrMqYvCfNSem8LxJ+MSnauvBlg4moYkdGCJAimkEkRpV0VK4bjjGrlu\n" + "0YMCggEAGftF1dJBqkUKc9dsbSQYwwfaU+W/gFWU4otTPd89HIOVkKyz3Hc0FrEH\n" + "68Ffrlx1MZU8wbNjjXytujJ7vwn0+n0bXN+5/oqEM+zlVunefCCLWWVLD0Sc/yOx\n" + "llgrU9u2z8Zjjl+mbbWNKhjV6oBNw3qi4CNHiBMHQk98xGQaRaTh/t/laXxZgtIo\n" + "Y+mZN7OXk3IUv6xlO+OyneG+CU9/VOPszLK9yFf95m9l5R6E6v9r4eE9N5OMOTxT\n" + "SBXZ+zNnnF4bIjy747KtCVI7XJQURDBbhhXick/lgX6sNj87vMaDJDnZ9kqqgc3U\n" + "1H23mg7nAvcEhsYClM3Z8/bEH6eRBQ==\n" + "-----END PRIVATE KEY-----\n"; final Pattern pattern = Pattern.compile(regex, Pattern.MULTILINE | Pattern.DOTALL | 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