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

/
/
gs

Test String

Code Generator

Language

Generated Code

$re = '/(?s)Query #.*?(?:(?:Alignments)|\Z)/s'; $str = 'Query #1: 020.1-Bni_its1_2019_envio1set1 Query ID: lcl|Query_25247 Length: 286 Sequences producing significant alignments: Scientific Common Max Total query E Per. Acc. Description Name Name Taxid Score Score cover Value Ident Len Accession Manihot esculenta mitochondrion, complete genome Manihot escu... cassava 3983 182 182 53% 2e-41 88.46 682840 NC_045136.1 Manihot esculenta mitochondrion, complete genome Manihot escu... cassava 3983 182 182 53% 2e-41 88.46 682840 MK176513.1 Asparagus officinalis cultivar Atlas mitochondrion, complete... Asparagus of... garden aspar... 4686 124 124 26% 4e-24 96.05 492062 NC_053642.1 Capsicum annuum var. glabriusculum bio-material USDA:PI 593546... Capsicum ann... NA 165789 89.8 149 27% 1e-13 100.00 497487 MN196478.1 Capsicum annuum cultivar Jeju mitochondrion, complete genome Capsicum annuum NA 4072 89.8 149 27% 1e-13 100.00 511530 KJ865410.1 Capsicum annuum cultivar CMS line FS4401 mitochondrion, comple... Capsicum annuum NA 4072 89.8 149 27% 1e-13 100.00 507452 KJ865409.1 Capsicum annuum clone CaSSR_42 microsatellite sequence Capsicum annuum NA 4072 89.8 89.8 17% 1e-13 98.04 668 KF824256.1 mitochondrion genome of Capsicum chinense chromosome 1, comple... Capsicum chi... NA 80379 89.8 149 29% 1e-13 98.04 307629 MZ736638.1 Dolichandrone spathacea chromosome DS1 mitochondrion, complete... Dolichandron... NA 241844 71.3 71.3 14% 5e-08 97.56 610698 MW432179.1 Dolichandrone cauda-felina mitochondrion, complete genome Markhamia ca... NA 2871431 71.3 71.3 14% 5e-08 97.56 837447 MW432178.1 Haematoxylum brasiletto mitochondrion, complete genome Haematoxylum... NA 191923 60.2 60.2 11% 1e-04 100.00 631094 NC_045040.1 Haematoxylum brasiletto mitochondrion, complete genome Haematoxylum... NA 191923 60.2 60.2 11% 1e-04 100.00 631094 MN017229.1 Leucaena trichandra mitochondrion, complete genome Leucaena tri... NA 190760 60.2 60.2 11% 1e-04 100.00 722009 NC_039738.1 Leucaena trichandra mitochondrion, complete genome Leucaena tri... NA 190760 60.2 60.2 11% 1e-04 100.00 722009 MH717173.1 Gleditsia sinensis mitochondrion, complete genome Gleditsia si... NA 66096 60.2 60.2 11% 1e-04 100.00 594121 MT921986.1 Alignments: >Manihot esculenta mitochondrion, complete genome Sequence ID: NC_045136.1 Length: 682840 Range 1: 329883 to 330034 '; preg_match_all($re, $str, $matches, PREG_SET_ORDER, 0); // Print the entire match result var_dump($matches);

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 PHP, please visit: http://php.net/manual/en/ref.pcre.php