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

# coding=utf8 # the above tag defines encoding for this document and is for Python 2.x compatibility import re regex = r"^(?<date>\d{4}-\d{2}-\d{2})\s*(?<time>\d{2}:\d{2}:\d{2}:\d{3})\s*\[\s*(?<level>\w*)\s*(?<module>.*?)\s*\]\s*(?<message>.*)$" test_str = ("2021-09-27 09:28:25:778 [ debug nextcloud.sync.database ] [ OCC::SyncJournalDb::tableColumns ]: Columns in the current journal: QVector(\"path\", \"chunk\", \"transferid\", \"errorcount\", \"size\", \"modtime\", \"contentChecksum\")\n" "2021-09-27 09:28:25:778 [ debug nextcloud.sync.database.sql ] [ OCC::SqlQuery::exec ]: SQL exec \"PRAGMA table_info('conflicts');\"\n" "2021-09-27 09:28:25:778 [ debug nextcloud.sync.database ] [ OCC::SyncJournalDb::tableColumns ]: Columns in the current journal: QVector(\"path\", \"baseFileId\", \"baseEtag\", \"baseModtime\", \"basePath\")\n" "2021-09-27 09:28:25:778 [ debug nextcloud.sync.database.sql ] [ OCC::SqlQuery::exec ]: SQL exec \"CREATE INDEX IF NOT EXISTS metadata_e2e_id ON metadata(e2eMangledName);\"\n" "2021-09-27 09:28:25:778 [ debug nextcloud.sync.database.sql ] [ OCC::SqlQuery::exec ]: Last exec affected 0 rows.\n" "2021-09-27 09:28:25:778 [ debug nextcloud.sync.database ] [ OCC::SyncJournalDb::commitInternal ]: Transaction commit \"update database structure: add e2eMangledName index\" and starting new transaction\n" "2021-09-27 09:28:25:778 [ debug nextcloud.sync.database.sql ] [ OCC::SqlQuery::exec ]: SQL exec \"PRAGMA table_info('blacklist');\"\n" "2021-09-27 09:28:25:778 [ debug nextcloud.sync.database ] [ OCC::SyncJournalDb::tableColumns ]: Columns in the current journal: QVector(\"path\", \"lastTryEtag\", \"lastTryModtime\", \"retrycount\", \"errorstring\", \"lastTryTime\", \"ignoreDuration\", \"renameTarget\", \"errorCategory\", \"requestId\")\n" "2021-09-27 09:28:25:778 [ debug nextcloud.sync.database.sql ] [ OCC::SqlQuery::exec ]: SQL exec \"CREATE INDEX IF NOT EXISTS blacklist_index ON blacklist(path collate nocase);\"\n" "2021-09-27 09:28:25:778 [ debug nextcloud.sync.database.sql ] [ OCC::SqlQuery::exec ]: Last exec affected 0 rows.\n" "2021-09-27 09:28:25:778 [ debug nextcloud.sync.database ] [ OCC::SyncJournalDb::commitInternal ]: Transaction commit \"checkConnect End\" \n" "2021-09-27 09:28:25:778 [ debug nextcloud.sync.database.sql ] [ OCC::SqlQuery::exec ]: SQL exec \"SELECT COUNT(*) FROM metadata\"\n" "2021-09-27 09:28:25:794 [ info nextcloud.gui.folder.manager ]: Adding folder to Folder Map OCC::Folder(0x2677fdf3ee0) \"1\"\n" "2021-09-27 09:28:25:795 [ info nextcloud.gui.folder.manager ]: Schedule folder \"1\" to sync!\n" "2021-09-27 09:28:25:795 [ info nextcloud.gui.folder.manager ]: Folder is not ready to sync, not scheduled!\n" "2021-09-27 09:28:25:797 [ info nextcloud.gui.application ]: Sync state changed for folder \"\" : \"Not yet Started\"\n" "2021-09-27 09:28:25:797 [ info nextcloud.sync.clientproxy ]: Set proxy configuration to use the preferred system proxy for http tcp connections\n" "2021-09-27 09:28:25:801 [ debug nextcloud.gui.updater ] [ OCC::Updater::create ]: QUrl(\"https://updates.nextcloud.org/client/?version=3.3.4.20210920&platform=win32&osRelease=windows&osVersion=server2016&kernelVersion=10.0.17763&oem=Nextcloud&buildArch=x86_64&currentArch=x86_64&versionsuffix=stable-Win64&updatesegment=43&msi=true\")\n" "2021-09-27 09:28:26:533 [ info nextcloud.sync.credentials.webflow ]: Fetch from keychain!\n" "2021-09-27 09:28:26:536 [ info nextcloud.gui.folder.navigationpane ]: Explorer Cloud storage provider: saving path \"\" to CLSID \"{5cefc208-e391-444c-af93-61c636da9853}\"\n" "2021-09-27 09:28:26:537 [ info nextcloud.gui.socketapi ]: New connection QLocalSocket(0x267027e4570)\n" "2021-09-27 09:28:26:538 [ warning nextcloud.sync.credentials.keychainchunk ]: Unable to read \"Nextcloud_clientCertificatePEM:0\" chunk \"0\" \"Password entry not found\"\n" "2021-09-27 09:28:26:538 [ warning nextcloud.sync.credentials.keychainchunk ]: Unable to read \"Nextcloud_clientKeyPEM\" chunk \"0\" \"Password entry not found\"\n" "2021-09-27 09:28:26:538 [ warning nextcloud.sync.credentials.webflow ]: Unable to read client key \"Password entry not found\"\n" "2021-09-27 09:28:26:538 [ warning nextcloud.sync.credentials.keychainchunk ]: Unable to read \"Nextcloud_su_mssrv01_clientCaCertificatePEM0\" chunk \"0\" \"Password entry not found\"\n" "2021-09-27 09:28:26:538 [ warning nextcloud.sync.credentials.webflow ]: Unable to read client CA cert slot \"0\" \"Password entry not found\"\n" "2021-09-27 09:28:26:538 [ debug nextcloud.sync.account ] [ OCC::Account::slotCredentialsFetched ]: User id already fetched.\n" "2021-09-27 09:28:26:539 [ info nextcloud.gui.account.state ]: Fetched credentials for \"\" attempting to connect\n" "2021-09-27 09:28:26:539 [ debug nextcloud.sync.account ] [ OCC::Account::resetNetworkAccessManager ]: Resetting QNAM\n" "2021-09-27 09:28:26:539 [ info nextcloud.sync.credentials.webflow ]: Get QNAM\n" "2021-09-27 09:28:26:539 [ debug nextcloud.sync.connectionvalidator ] [ OCC::ConnectionValidator::checkServerAndAuth ]: Checking server and authentication\n" "2021-09-27 09:28:26:539 [ debug nextcloud.sync.connectionvalidator ] [ OCC::ConnectionValidator::checkServerAndAuth ]: Trying to look up system proxy\n" "2021-09-27 09:28:26:540 [ info nextcloud.sync.connectionvalidator ]: No system proxy set by OS\n" "2021-09-27 09:28:26:541 [ info nextcloud.sync.accessmanager ]: 2 \"\" \"\" has X-Request-ID \"75765e8e-2b52-4dd9-b67b-62b450feafdc\"\n" "2021-09-27 09:28:26:541 [ debug nextcloud.sync.cookiejar ] [ OCC::CookieJar::cookiesForUrl ]: QUrl(\"\") requests: (QNetworkCookie(\"nc_sameSiteCookielax=true; secure; HttpOnly; expires=Fri, 31-Dec-2100 23:59:59 GMT), QNetworkCookie(\"nc_sameSiteCookiestrict=true; secure; HttpOnly; expires=Fri, 31-Dec-2100 23:59:59 GMT))\n" "2021-09-27 09:28:26:541 [ info nextcloud.sync.networkjob ]: OCC::CheckServerJob created for \"\" + \"status.php\" \"OCC::ConnectionValidator\"\n" "2021-09-27 09:28:26:795 [ debug nextcloud.gui.folderwatcher ] [ OCC::FolderWatcher::pathIsIgnored ]: * Ignoring file \"D:/Shared/NextcloudMirror/.owncloudsync.log\"\n" "2021-09-27 09:28:28:826 [ info nextcloud.gui.updater ]: Checking for available update\n" "2021-09-27 09:28:28:826 [ info nextcloud.sync.accessmanager ]: 2 \"\" \"https://updates.nextcloud.org/client/?version=3.3.4.20210920&platform=win32&osRelease=windows&osVersion=server2016&kernelVersion=10.0.17763&oem=Nextcloud&buildArch=x86_64&currentArch=x86_64&versionsuffix=stable-Win64&updatesegment=43&msi=true\" has X-Request-ID \"2fbd3d8d-a4e6-486f-b0f7-dbd441225cd3\"\n" "2021-09-27 09:28:28:826 [ debug nextcloud.sync.cookiejar ] [ OCC::CookieJar::cookiesForUrl ]: QUrl(\"https://updates.nextcloud.org/client/?version=3.3.4.20210920&platform=win32&osRelease=windows&osVersion=server2016&kernelVersion=10.0.17763&oem=Nextcloud&buildArch=x86_64&currentArch=x86_64&versionsuffix=stable-Win64&updatesegment=43&msi=true\") requests: ()\n" "2021-09-27 09:28:29:638 [ info nextcloud.sync.credentials.webflow ]: request finished") matches = re.finditer(regex, test_str, re.MULTILINE | re.IGNORECASE) for matchNum, match in enumerate(matches, start=1): print ("Match {matchNum} was found at {start}-{end}: {match}".format(matchNum = matchNum, start = match.start(), end = match.end(), match = match.group())) for groupNum in range(0, len(match.groups())): groupNum = groupNum + 1 print ("Group {groupNum} found at {start}-{end}: {group}".format(groupNum = groupNum, start = match.start(groupNum), end = match.end(groupNum), group = match.group(groupNum))) # Note: for Python 2.7 compatibility, use ur"" to prefix the regex and u"" to prefix the test string and substitution.

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