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
Processing...

Test String

Code Generator

Language

Generated Code

import re regex = re.compile(r"\"year\"\:(\d{4})\,") test_str = "{\"total_pages\":1,\"total_count\":3,\"per_page\":60,\"page\":1,\"data\":[{\"id\":\"524414\",\"type\":\"subtitle\",\"attributes\":{\"subtitle_id\":\"524414\",\"language\":\"ro\",\"download_count\":1421,\"new_download_count\":1,\"hearing_impaired\":false,\"hd\":false,\"fps\":25.0,\"votes\":0,\"ratings\":0.0,\"from_trusted\":false,\"foreign_parts_only\":false,\"upload_date\":\"2010-03-07T08:17:40Z\",\"ai_translated\":false,\"machine_translated\":false,\"release\":\"Casino Royale - oo7\",\"comments\":\"AUTOLOAD AUTOUPLOAD\",\"legacy_subtitle_id\":3650579,\"uploader\":{\"uploader_id\":3282,\"name\":\"os-auto\",\"rank\":\"Application Developers\"},\"feature_details\":{\"feature_id\":518630,\"feature_type\":\"Movie\",\"year\":1967,\"title\":\"Casino Royale\",\"movie_name\":\"1967 - Casino Royale\",\"imdb_id\":61452,\"tmdb_id\":12208},\"url\":\"https://www.opensubtitles.com/ro/subtitles/legacy/3650579\",\"related_links\":{\"label\":\"All subtitles for Casino Royale\",\"url\":\"https://www.opensubtitles.com/ro/movies/1967-casino-royale\",\"img_url\":\"https://s9.osdb.link/features/0/3/6/518630.jpg\"},\"files\":[{\"file_id\":579397,\"cd_number\":1,\"file_name\":\"Casino Royale - oo7.sub\"}],\"moviehash_match\":true}},{\"id\":\"522774\",\"type\":\"subtitle\",\"attributes\":{\"subtitle_id\":\"522774\",\"language\":\"es\",\"download_count\":1003,\"new_download_count\":1,\"hearing_impaired\":false,\"hd\":false,\"fps\":25.0,\"votes\":2,\"ratings\":9.5,\"from_trusted\":false,\"foreign_parts_only\":false,\"upload_date\":\"2003-12-18T23:00:00Z\",\"ai_translated\":false,\"machine_translated\":false,\"release\":\"Casino Royale (1967)\",\"comments\":null,\"legacy_subtitle_id\":59217,\"uploader\":{\"uploader_id\":8092,\"name\":\"ShooCat (a)\",\"rank\":\"bronze member\"},\"feature_details\":{\"feature_id\":518630,\"feature_type\":\"Movie\",\"year\":1967,\"title\":\"Casino Royale\",\"movie_name\":\"1967 - Casino Royale\",\"imdb_id\":61452,\"tmdb_id\":12208},\"url\":\"https://www.opensubtitles.com/es/subtitles/legacy/59217\",\"related_links\":{\"label\":\"All subtitles for Casino Royale\",\"url\":\"https://www.opensubtitles.com/es/movies/1967-casino-royale\",\"img_url\":\"https://s9.osdb.link/features/0/3/6/518630.jpg\"},\"files\":[{\"file_id\":577519,\"cd_number\":1,\"file_name\":\"Casino Royale (SPA).srt\"}],\"moviehash_match\":true}},{\"id\":\"525409\",\"type\":\"subtitle\",\"attributes\":{\"subtitle_id\":\"525409\",\"language\":\"es\",\"download_count\":432,\"new_download_count\":2,\"hearing_impaired\":false,\"hd\":false,\"fps\":25.0,\"votes\":0,\"ratings\":0.0,\"from_trusted\":false,\"foreign_parts_only\":false,\"upload_date\":\"2014-05-04T22:40:02Z\",\"ai_translated\":false,\"machine_translated\":false,\"release\":\"James Bond - 007 - Casino Royale -1967\",\"comments\":\"\",\"legacy_subtitle_id\":5657430,\"uploader\":{\"uploader_id\":3282,\"name\":\"os-auto\",\"rank\":\"Application Developers\"},\"feature_details\":{\"feature_id\":518630,\"feature_type\":\"Movie\",\"year\":1967,\"title\":\"Casino Royale\",\"movie_name\":\"1967 - Casino Royale\",\"imdb_id\":61452,\"tmdb_id\":12208},\"url\":\"https://www.opensubtitles.com/es/subtitles/legacy/5657430\",\"related_links\":{\"label\":\"All subtitles for Casino Royale\",\"url\":\"https://www.opensubtitles.com/es/movies/1967-casino-royale\",\"img_url\":\"https://s9.osdb.link/features/0/3/6/518630.jpg\"},\"files\":[{\"file_id\":580507,\"cd_number\":1,\"file_name\":\"James Bond - 007 - Casino Royale -1967-spa.srt\"}],\"moviehash_match\":true}}]}" match = regex.search(test_str) if match: print(f"Match was found at {match.start()}-{match.end()}: {match.group()}") for group_num, group in enumerate(match.groups(), start=1): print(f"Group {group_num} found at {match.start(group_num)}-{match.end(group_num)}: {group}")

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 Python, please visit: https://docs.python.org/3/library/re.html