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

Substitution
Processing...

Code Generator

Language

Generated Code

import re regex = re.compile(r"-.*") test_str = ("es-\n" "af\n" "af-NA\n" "af-ZA\n" "agq\n" "agq-CM\n" "ak\n" "ak-GH\n" "am\n" "am-ET\n" "ar\n" "ar-001\n" "ar-AE\n" "ar-BH\n" "ar-DJ\n" "ar-DZ\n" "ar-EG\n" "ar-EH\n" "ar-ER\n" "ar-IL\n" "ar-IQ\n" "ar-JO\n" "ar-KM\n" "ar-KW\n" "ar-LB\n" "ar-LY\n" "ar-MA\n" "ar-MR\n" "ar-OM\n" "ar-PS\n" "ar-QA\n" "ar-SA\n" "ar-SD\n" "ar-SO\n" "ar-SS\n" "ar-SY\n" "ar-TD\n" "ar-TN\n" "ar-YE\n" "as\n" "as-IN\n" "asa\n" "asa-TZ\n" "ast\n" "ast-ES\n" "az\n" "az-Cyrl\n" "az-Cyrl-AZ\n" "az-Latn\n" "az-Latn-AZ\n" "bas\n" "bas-CM\n" "be\n" "be-BY\n" "bem\n" "bem-ZM\n" "bez\n" "bez-TZ\n" "bg\n" "bg-BG\n" "bm\n" "bm-ML\n" "bn\n" "bn-BD\n" "bn-IN\n" "bo\n" "bo-CN\n" "bo-IN\n" "br\n" "br-FR\n" "brx\n" "brx-IN\n" "bs\n" "bs-Cyrl\n" "bs-Cyrl-BA\n" "bs-Latn\n" "bs-Latn-BA\n" "ca\n" "ca-AD\n" "ca-ES\n" "ca-FR\n" "ca-IT\n" "ccp\n" "ccp-BD\n" "ccp-IN\n" "ce\n" "ce-RU\n" "cgg\n" "cgg-UG\n" "chr\n" "chr-US\n" "ckb\n" "ckb-IQ\n" "ckb-IR\n" "cs\n" "cs-CZ\n" "cy\n" "cy-GB\n" "da\n" "da-DK\n" "da-GL\n" "dav\n" "dav-KE\n" "de\n" "de-AT\n" "de-BE\n" "de-CH\n" "de-DE\n" "de-IT\n" "de-LI\n" "de-LU\n" "dje\n" "dje-NE\n" "dsb\n" "dsb-DE\n" "dua\n" "dua-CM\n" "dyo\n" "dyo-SN\n" "dz\n" "dz-BT\n" "ebu\n" "ebu-KE\n" "ee\n" "ee-GH\n" "ee-TG\n" "el\n" "el-CY\n" "el-GR\n" "en\n" "en-001\n" "en-150\n" "en-AG\n" "en-AI\n" "en-AS\n" "en-AT\n" "en-AU\n" "en-BB\n" "en-BE\n" "en-BI\n" "en-BM\n" "en-BS\n" "en-BW\n" "en-BZ\n" "en-CA\n" "en-CC\n" "en-CH\n" "en-CK\n" "en-CM\n" "en-CX\n" "en-CY\n" "en-DE\n" "en-DG\n" "en-DK\n" "en-DM\n" "en-ER\n" "en-FI\n" "en-FJ\n" "en-FK\n" "en-FM\n" "en-GB\n" "en-GD\n" "en-GG\n" "en-GH\n" "en-GI\n" "en-GM\n" "en-GU\n" "en-GY\n" "en-HK\n" "en-IE\n" "en-IL\n" "en-IM\n" "en-IN\n" "en-IO\n" "en-JE\n" "en-JM\n" "en-KE\n" "en-KI\n" "en-KN\n" "en-KY\n" "en-LC\n" "en-LR\n" "en-LS\n" "en-MG\n" "en-MH\n" "en-MO\n" "en-MP\n" "en-MS\n" "en-MT\n" "en-MU\n" "en-MW\n" "en-MY\n" "en-NA\n" "en-NF\n" "en-NG\n" "en-NL\n" "en-NR\n" "en-NU\n" "en-NZ\n" "en-PG\n" "en-PH\n" "en-PK\n" "en-PN\n" "en-PR\n" "en-PW\n" "en-RW\n" "en-SB\n" "en-SC\n" "en-SD\n" "en-SE\n" "en-SG\n" "en-SH\n" "en-SI\n" "en-SL\n" "en-SS\n" "en-SX\n" "en-SZ\n" "en-TC\n" "en-TK\n" "en-TO\n" "en-TT\n" "en-TV\n" "en-TZ\n" "en-UG\n" "en-UM\n" "en-US\n" "en-US-POSIX\n" "en-VC\n" "en-VG\n" "en-VI\n" "en-VU\n" "en-WS\n" "en-ZA\n" "en-ZM\n" "en-ZW\n" "eo\n" "es\n" "es-419\n" "es-AR\n" "es-BO\n" "es-BR\n" "es-BZ\n" "es-CL\n" "es-CO\n" "es-CR\n" "es-CU\n" "es-DO\n" "es-EA\n" "es-EC\n" "es-ES\n" "es-GQ\n" "es-GT\n" "es-HN\n" "es-IC\n" "es-MX\n" "es-NI\n" "es-PA\n" "es-PE\n" "es-PH\n" "es-PR\n" "es-PY\n" "es-SV\n" "es-US\n" "es-UY\n" "es-VE\n" "et\n" "et-EE\n" "eu\n" "eu-ES\n" "ewo\n" "ewo-CM\n" "fa\n" "fa-AF\n" "fa-IR\n" "ff\n" "ff-CM\n" "ff-GN\n" "ff-MR\n" "ff-SN\n" "fi\n" "fi-FI\n" "fil\n" "fil-PH\n" "fo\n" "fo-DK\n" "fo-FO\n" "fr\n" "fr-BE\n" "fr-BF\n" "fr-BI\n" "fr-BJ\n" "fr-BL\n" "fr-CA\n" "fr-CD\n" "fr-CF\n" "fr-CG\n" "fr-CH\n" "fr-CI\n" "fr-CM\n" "fr-DJ\n" "fr-DZ\n" "fr-FR\n" "fr-GA\n" "fr-GF\n" "fr-GN\n" "fr-GP\n" "fr-GQ\n" "fr-HT\n" "fr-KM\n" "fr-LU\n" "fr-MA\n" "fr-MC\n" "fr-MF\n" "fr-MG\n" "fr-ML\n" "fr-MQ\n" "fr-MR\n" "fr-MU\n" "fr-NC\n" "fr-NE\n" "fr-PF\n" "fr-PM\n" "fr-RE\n" "fr-RW\n" "fr-SC\n" "fr-SN\n" "fr-SY\n" "fr-TD\n" "fr-TG\n" "fr-TN\n" "fr-VU\n" "fr-WF\n" "fr-YT\n" "fur\n" "fur-IT\n" "fy\n" "fy-NL\n" "ga\n" "ga-IE\n" "gd\n" "gd-GB\n" "gl\n" "gl-ES\n" "gsw\n" "gsw-CH\n" "gsw-FR\n" "gsw-LI\n" "gu\n" "gu-IN\n" "guz\n" "guz-KE\n" "gv\n" "gv-IM\n" "ha\n" "ha-GH\n" "ha-NE\n" "ha-NG\n" "haw\n" "haw-US\n" "he\n" "he-IL\n" "hi\n" "hi-IN\n" "hr\n" "hr-BA\n" "hr-HR\n" "hsb\n" "hsb-DE\n" "hu\n" "hu-HU\n" "hy\n" "hy-AM\n" "id\n" "id-ID\n" "ig\n" "ig-NG\n" "ii\n" "ii-CN\n" "is\n" "is-IS\n" "it\n" "it-CH\n" "it-IT\n" "it-SM\n" "it-VA\n" "ja\n" "ja-JP\n" "jgo\n" "jgo-CM\n" "jmc\n" "jmc-TZ\n" "ka\n" "ka-GE\n" "kab\n" "kab-DZ\n" "kam\n" "kam-KE\n" "kde\n" "kde-TZ\n" "kea\n" "kea-CV\n" "khq\n" "khq-ML\n" "ki\n" "ki-KE\n" "kk\n" "kk-KZ\n" "kkj\n" "kkj-CM\n" "kl\n" "kl-GL\n" "kln\n" "kln-KE\n" "km\n" "km-KH\n" "kn\n" "kn-IN\n" "ko\n" "ko-KP\n" "ko-KR\n" "kok\n" "kok-IN\n" "ks\n" "ks-IN\n" "ksb\n" "ksb-TZ\n" "ksf\n" "ksf-CM\n" "ksh\n" "ksh-DE\n" "kw\n" "kw-GB\n" "ky\n" "ky-KG\n" "lag\n" "lag-TZ\n" "lb\n" "lb-LU\n" "lg\n" "lg-UG\n" "lkt\n" "lkt-US\n" "ln\n" "ln-AO\n" "ln-CD\n" "ln-CF\n" "ln-CG\n" "lo\n" "lo-LA\n" "lrc\n" "lrc-IQ\n" "lrc-IR\n" "lt\n" "lt-LT\n" "lu\n" "lu-CD\n" "luo\n" "luo-KE\n" "luy\n" "luy-KE\n" "lv\n" "lv-LV\n" "mas\n" "mas-KE\n" "mas-TZ\n" "mer\n" "mer-KE\n" "mfe\n" "mfe-MU\n" "mg\n" "mg-MG\n" "mgh\n" "mgh-MZ\n" "mgo\n" "mgo-CM\n" "mk\n" "mk-MK\n" "ml\n" "ml-IN\n" "mn\n" "mn-MN\n" "mr\n" "mr-IN\n" "ms\n" "ms-BN\n" "ms-MY\n" "ms-SG\n" "mt\n" "mt-MT\n" "mua\n" "mua-CM\n" "my\n" "my-MM\n" "mzn\n" "mzn-IR\n" "naq\n" "naq-NA\n" "nb\n" "nb-NO\n" "nb-SJ\n" "nd\n" "nd-ZW\n" "nds\n" "nds-DE\n" "nds-NL\n" "ne\n" "ne-IN\n" "ne-NP\n" "nl\n" "nl-AW\n" "nl-BE\n" "nl-BQ\n" "nl-CW\n" "nl-NL\n" "nl-SR\n" "nl-SX\n" "nmg\n" "nmg-CM\n" "nn\n" "nn-NO\n" "nnh\n" "nnh-CM\n" "nus\n" "nus-SS\n" "nyn\n" "nyn-UG\n" "om\n" "om-ET\n" "om-KE\n" "or\n" "or-IN\n" "os\n" "os-GE\n" "os-RU\n" "pa\n" "pa-Arab\n" "pa-Arab-PK\n" "pa-Guru\n" "pa-Guru-IN\n" "pl\n" "pl-PL\n" "ps\n" "ps-AF\n" "pt\n" "pt-AO\n" "pt-BR\n" "pt-CH\n" "pt-CV\n" "pt-GQ\n" "pt-GW\n" "pt-LU\n" "pt-MO\n" "pt-MZ\n" "pt-PT\n" "pt-ST\n" "pt-TL\n" "qu\n" "qu-BO\n" "qu-EC\n" "qu-PE\n" "rm\n" "rm-CH\n" "rn\n" "rn-BI\n" "ro\n" "ro-MD\n" "ro-RO\n" "rof\n" "rof-TZ\n" "ru\n" "ru-BY\n" "ru-KG\n" "ru-KZ\n" "ru-MD\n" "ru-RU\n" "ru-UA\n" "rw\n" "rw-RW\n" "rwk\n" "rwk-TZ\n" "sah\n" "sah-RU\n" "saq\n" "saq-KE\n" "sbp\n" "sbp-TZ\n" "se\n" "se-FI\n" "se-NO\n" "se-SE\n" "seh\n" "seh-MZ\n" "ses\n" "ses-ML\n" "sg\n" "sg-CF\n" "shi\n" "shi-Latn\n" "shi-Latn-MA\n" "shi-Tfng\n" "shi-Tfng-MA\n" "si\n" "si-LK\n" "sk\n" "sk-SK\n" "sl\n" "sl-SI\n" "smn\n" "smn-FI\n" "sn\n" "sn-ZW\n" "so\n" "so-DJ\n" "so-ET\n" "so-KE\n" "so-SO\n" "sq\n" "sq-AL\n" "sq-MK\n" "sq-XK\n" "sr\n" "sr-Cyrl\n" "sr-Cyrl-BA\n" "sr-Cyrl-ME\n" "sr-Cyrl-RS\n" "sr-Cyrl-XK\n" "sr-Latn\n" "sr-Latn-BA\n" "sr-Latn-ME\n" "sr-Latn-RS\n" "sr-Latn-XK\n" "sv\n" "sv-AX\n" "sv-FI\n" "sv-SE\n" "sw\n" "sw-CD\n" "sw-KE\n" "sw-TZ\n" "sw-UG\n" "ta\n" "ta-IN\n" "ta-LK\n" "ta-MY\n" "ta-SG\n" "te\n" "te-IN\n" "teo\n" "teo-KE\n" "teo-UG\n" "tg\n" "tg-TJ\n" "th\n" "th-TH\n" "ti\n" "ti-ER\n" "ti-ET\n" "to\n" "to-TO\n" "tr\n" "tr-CY\n" "tr-TR\n" "tt\n" "tt-RU\n" "twq\n" "twq-NE\n" "tzm\n" "tzm-MA\n" "ug\n" "ug-CN\n" "uk\n" "uk-UA\n" "ur\n" "ur-IN\n" "ur-PK\n" "uz\n" "uz-Arab\n" "uz-Arab-AF\n" "uz-Cyrl\n" "uz-Cyrl-UZ\n" "uz-Latn\n" "uz-Latn-UZ\n" "vai\n" "vai-Latn\n" "vai-Latn-LR\n" "vai-Vaii\n" "vai-Vaii-LR\n" "vi\n" "vi-VN\n" "vun\n" "vun-TZ\n" "wae\n" "wae-CH\n" "wo\n" "wo-SN\n" "xog\n" "xog-UG\n" "yav\n" "yav-CM\n" "yi\n" "yi-001\n" "yo\n" "yo-BJ\n" "yo-NG\n" "yue\n" "yue-Hans\n" "yue-Hans-CN\n" "yue-Hant\n" "yue-Hant-HK\n" "zgh\n" "zgh-MA\n" "zh\n" "zh-Hans\n" "zh-Hans-CN\n" "zh-Hans-HK\n" "zh-Hans-MO\n" "zh-Hans-SG\n" "zh-Hant\n" "zh-Hant-HK\n" "zh-Hant-MO\n" "zh-Hant-TW\n" "zu\n" "zu-ZA") subst = "" result = regex.sub(subst, test_str, count=1) if result: print(result)

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