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

/
/
gmysi

Test String

Code Generator

Language

Generated Code

const regex = /([\-]*BEGIN\sCERTIFICATE\sREQUEST[\-]+.+[-]+END\sCERTIFICATE\sREQUEST[-]+)/gmysi; // Alternative syntax using RegExp constructor // const regex = new RegExp('([\\-]*BEGIN\\sCERTIFICATE\\sREQUEST[\\-]+.+[-]+END\\sCERTIFICATE\\sREQUEST[-]+)', 'gmysi') const str = `-----BEGIN CERTIFICATE REQUEST----- MIIEuDCCAqACAQAwczELMAkGA1UEBhMCVVMxGDAWBgNVBAMMD3BsdWdpYmlsaXR5 LmNvbTEXMBUGA1UEBwwOU2FsdCBMYWtlIENpdHkxFDASBgNVBAoMC1BsdWdpYmls aXR5MQ0wCwYDVQQIDARVdGFoMQwwCgYDVQQLDANPcmcwggIiMA0GCSqGSIb3DQEB AQUAA4ICDwAwggIKAoICAQCfQqx8YexJ4HjGqIpywxvTOPDnqIaZicD3IQSUdAb5 5vcfAaD/0KBH/6Oa2NPlq4mYAw2octDiuklvkXIUgnn85vwlj6fLm6iR6i1tjM3g tusxur3fmMdF9YqDNNM7LVSxXMq/vXuChPj3bVib2EyKJRcBn8EMTnJYdfl3YK4l j+KW7cnxIy8E3DAy4KIUPbI2LNPix43emW6XuMB3hpvcbs2YpQogagAQwvNYAIcW Ub3+fSEbXFNVmYFRPbd7T5Arei4Ubl8kKVWfqUnWIOdYQh7o0CbQl+67ivAyRnDU oItNtPz+seWzL1xerjQqdlHrCQFGNfLdI3Hfl9SZVKOqdsjs2bEiP+C6E/pilvu/ zEtD5VbGd0UBBZtANm6BdBEhhigX8vL/FfiqxlPsEK31L9tQnwa6ETvcVbRQoXBW idJJKCmiScz17ML8aTxw0zXc16CBHuE4AEV7xaNmdl5NsYCB+q/H3SCVsreMnu7A cpCgvaCZX1/8zSWrVNMf0i+/gJCoBh1OXNnqtCPycJDPvrVGYF2U7RqzC4c91Kqe QxEKHApEJAL47nFtM9c3K2fNvLEVOD+k+iDkEuL++VHaXO3VHCiVoJjQCSNTChl3 aSL29LadjcPvf2QdMymEJ4+wKI8u6l1bk51zN0INnVDDkMdtfCu0C8ux8M4roP9Y kQIDAQABoAAwDQYJKoZIhvcNAQELBQADggIBAJO3HIp2hvkQh6/Bk19RiEdyfJjb xoPWtfM4lWDyXLxq6HrmKadvOtjTs9fGpoBRJaknIhy8n0/oN8Et+uFgga3ptb/8 AjyDRVqmYK3byAJrUm055v9VseNwFqE/hsZiFtPMVA5I5agtnQm8o6zPgUSMQWso evA00Fa+Q1X1Hmbthtd2ZH64cxLOqW3vW9LViBp9C52mU1NyZtvPRJAlcOlH1r9A MFnPrR7T4HJ8gMEvaj0likFr5nQKWH5ScPvHbIKyIoebn9RznbMZBNjUn60+I0Kt VwN8UrIwZMNF+eL99I6kEr/gjoZ3VegPH7YaVRQ280L4NvZNKMbAr1Z+uyCD587y Zf+cbzZB30xTfra0/iUQnGEBuScpGQMdXEzmE/lBCnNnqnNohrAwvQNLISbnK7w2 JUrwbIIgRrLmmXGELPQ7vBkKmCtSrmPGLyWctwG005h8hHLtFk8jagSDJ/gTQ3Wv n7YEy3ROHujz/UVGrGE2P3oKs5prn+N52HIxM9XoaQndrtbyvkaOe+WHGZ0htQkE H6Rrh0YijAFpZTsKwv1ndMh2HpoaYX3B1s9ky3TWGAdOMCgHgdBFpvk2+PdDN+6a Js+0VtfRywLxxaEamLciBj6JmjybIEBSANSwf2pdn8OnMq5BLZrLRWhsaMVGlciL 1JPHcsgLz1lD8FYC -----END CERTIFICATE REQUEST----- -----BEGIN PRIVATE KEY----- MIIJQgIBADANBgkqhkiG9w0BAQEFAASCCSwwggkoAgEAAoICAQCfQqx8YexJ4HjG qIpywxvTOPDnqIaZicD3IQSUdAb55vcfAaD/0KBH/6Oa2NPlq4mYAw2octDiuklv kXIUgnn85vwlj6fLm6iR6i1tjM3gtusxur3fmMdF9YqDNNM7LVSxXMq/vXuChPj3 bVib2EyKJRcBn8EMTnJYdfl3YK4lj+KW7cnxIy8E3DAy4KIUPbI2LNPix43emW6X uMB3hpvcbs2YpQogagAQwvNYAIcWUb3+fSEbXFNVmYFRPbd7T5Arei4Ubl8kKVWf qUnWIOdYQh7o0CbQl+67ivAyRnDUoItNtPz+seWzL1xerjQqdlHrCQFGNfLdI3Hf l9SZVKOqdsjs2bEiP+C6E/pilvu/zEtD5VbGd0UBBZtANm6BdBEhhigX8vL/Ffiq xlPsEK31L9tQnwa6ETvcVbRQoXBWidJJKCmiScz17ML8aTxw0zXc16CBHuE4AEV7 xaNmdl5NsYCB+q/H3SCVsreMnu7AcpCgvaCZX1/8zSWrVNMf0i+/gJCoBh1OXNnq tCPycJDPvrVGYF2U7RqzC4c91KqeQxEKHApEJAL47nFtM9c3K2fNvLEVOD+k+iDk EuL++VHaXO3VHCiVoJjQCSNTChl3aSL29LadjcPvf2QdMymEJ4+wKI8u6l1bk51z N0INnVDDkMdtfCu0C8ux8M4roP9YkQIDAQABAoICAGRnX2DnR1Vn/ByaQvaJBPDM NCyINZt0mj/zA/UnlQJV1zQoDb1ZZMMfaqCD1Es2Mv+v5RtujzxxXzzEQFynyYpk gVCY2Ztmngan0U4AeAcUqwBmD7B4nCEB5PpFAmqLcJqEupnZNpWZiXBL8pIF8nMh YPi4I7fDeRlF/ymAvSmXJa4raaXpnYn92zEoJ2aFYuX+qvKNBmbw6iUi58wzA+4b uOhkHBdFXJc0oL+5TXEHxbU8Y/Pg5/TOWxXBx/wos+aFF6nvz3F30bBfxNoHUnJ0 9RGnsODO+EYqGLZJbHbQZCJwWROlSgAGesCCKQcgIxL/UVtXRa6e2vqwuOqVzrv5 msBFM/HzcUvdtNq4FP2UfcqAi4FZlwHlbTDphE3fZSPbLIoJZLuhKuJPFA/Sc8L/ ABPnmRqb0bZ2RKECBnXrsV0U/KeSxbY4r0Hj+ggBnLNO1VhlYjCQZlCXA4X8LdyV wBvoNeKjSo3ZD8vr/Jvpdm/9xiWVikbPqYpiEiIn6iN8omYWjxHWgDox9fd+zVQu c/3giKEVAQYhNYj+YbkZpmnWQNjdL89TatjdBeaWO9Zq4k1VwN5UYB539O61kHfC bhpYx/ptIgTBdEwp+ohlkAegCyBS+Mo3SiQocATdpeBwAMoMpMOtCiMDyGjydK0Y 2xi5+uOGMDKMbWvRe10FAoIBAQDMnaqknzt8Brc1KHQVv7Ww0VTrCEjItXLaAIOs AW9PyL6/9lhFYljCnEGcWL3LAZlhldr81aNE40qw5FVVRrTR2Hg3xF/znZwa6Bnc 0t1XXGRj0BZIH5OrZSdf0gXdEwIrIB2LmllxMMpzd0BSgX/+x6k2K6FMAl/048bg v986GsRwUjrlkt0ihyQNHlWuKKK82W1G6G4iQiC0bD5i/AUBer9o5Yb4X9GrgoIA nWJIHstfJ80KTOJMQVczj0SKLmTjnIUE91BcXGhqTTdcSKTWbts50HyuwQAYcZco vW5B5Sbyf57jCvu68Bo3gxngE1xYjtTR6Q13azII4DxyE7MjAoIBAQDHQTMNW8NQ unvr64yqCwzBmEmpCJ6NEbYub3rqHzQPe5Na5VN1iTujKx5ifhi5uhR5A5Jluy2O fUWzF/ihEdVOOh0JPj1NiJkY1VkuiY9Y2aHR2+8st06sp92Zj1i7Us/t+CP+WuOv m7He4xRRrXx9tXcdpAzaTr8NoKXCL1fz4t8HKUZdfvvCtY+Ghd3ct1rEG8Bi9SUF yBoTE1NwATHLCsYFURhpmWwnQTMpRTjlhogNSywDG59fdcqyEBUacCnPG7ZxZ3c2 N8VWknZsf9hBEyjyGCvTNq1A0KKJ6PIEp2gOoMi4I1nbKB1jSC7Gh61pJ+aV4L6g M10Jh890RWq7AoIBAQC8vvv4G0Jd6Dv79zMOFOffEVpJ7DxnmKk3W54afsBVUpJS tUU7y7qg2k7TkDCTIQiBsiBtdgzDsP7nKdllbnHB2PMcTjNMoCit0Uh6ILE4suuP /xVutmIbipXFmBD8m1o2uctHSbwT47P8yxY0hWyycy8t3xVM7ivh1HNSQuwBx0tJ aTEXMGB4Rz0ENOVIYAeuOMrKzAE77NAKXoc1+9AKS1Zhxsi4OHtKwHp3YraUXIOx ZR+Izt85BFUSJKhO5vj91RYHPLOOX1eaJ1xX7lLP0za6oA1Djpkt8ypC1Grushk5 PGwud6U6Dd3BM1gdEP7wWeELOPXJIMLo2SApAu8NAoIBAGjYmPl9gJ/ZEN4KOyE6 4UJ5VME6RNusJzX1+TJ6qtU+zEH3C9x8EsKALOPcwDvye1VWGNGpFYa1ylg709tF W/1mvOKhOnay2wRjNyMyxRgWpHyeAxN/fUmCpytnb2RaZgktGht8TfSYs5a53HZC GJC5TO1u5kh1STjtgGtWqCwwA/VrtZf6+pTxHo3FoQHEBWHNzIUFw65wJbBF6hC0 wDO7/ojLrFHcpjldqIMd5pt4F90O4iDchxcfD0J1DfW0cXuGdJDlxafk3tT4CpJ7 Dxrm7xO8vkrMqYvCfNSem8LxJ+MSnauvBlg4moYkdGCJAimkEkRpV0VK4bjjGrlu 0YMCggEAGftF1dJBqkUKc9dsbSQYwwfaU+W/gFWU4otTPd89HIOVkKyz3Hc0FrEH 68Ffrlx1MZU8wbNjjXytujJ7vwn0+n0bXN+5/oqEM+zlVunefCCLWWVLD0Sc/yOx llgrU9u2z8Zjjl+mbbWNKhjV6oBNw3qi4CNHiBMHQk98xGQaRaTh/t/laXxZgtIo Y+mZN7OXk3IUv6xlO+OyneG+CU9/VOPszLK9yFf95m9l5R6E6v9r4eE9N5OMOTxT SBXZ+zNnnF4bIjy747KtCVI7XJQURDBbhhXick/lgX6sNj87vMaDJDnZ9kqqgc3U 1H23mg7nAvcEhsYClM3Z8/bEH6eRBQ== -----END PRIVATE KEY----- `; // Reset `lastIndex` if this regex is defined globally // regex.lastIndex = 0; let m; while ((m = regex.exec(str)) !== null) { // This is necessary to avoid infinite loops with zero-width matches if (m.index === regex.lastIndex) { regex.lastIndex++; } // The result can be accessed through the `m`-variable. m.forEach((match, groupIndex) => { console.log(`Found match, group ${groupIndex}: ${match}`); }); }

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 JavaScript, please visit: https://developer.mozilla.org/en/docs/Web/JavaScript/Guide/Regular_Expressions