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

/
/
igm

Test String

Code Generator

Language

Generated Code

const regex = /^[-ʻ'`a-zġūĀñēöåàíáüóéōāī ]+$/igm; // Alternative syntax using RegExp constructor // const regex = new RegExp('^[-ʻ\'`a-zġūĀñēöåàíáüóéōāī ]+$', 'igm') const str = `https://en.wikipedia.org/wiki/List_of_U.S._cities_with_diacritics Alaska Alaska Utqiaġvik American Samoa Āfono Ālega 'Āmanave Āmouli Aūa Fagasā Faleāsao Lumā Tāfuna California La Cañada Flintridge Piñon Hills San José Colorado Cañon Cañon City Piñon Piñon Piñon Acres Guam Hagåtña Hagåtña Heights Hawaii ʻĀhuimanu ʻ\`\`\`\`Āinaloa Hanapēpē Haʻikū-Pauwela Hālawa Hāliʻimaile Hāmoa Hāna Hāʻōʻū Hāwī Hīlea Hōlualoa Hōnaunau-Nāpōʻopoʻo Honokōhau Hoʻōpūloa Kāʻanapali Kaimū Kākiʻo Kalāheo Kamalō Kāneʻohe Kaupō Kaʻūpūlehu Keālia Kēōkea Kēōkea Kīhei Kīholo Kīlauea Kīpahulu Kīpū Kōloa Kūkaʻiau Kūkiʻo Lāʻie Lānaʻi City Laupāhoehoe Lāwaʻi Līhuʻe Māʻalaea Māʻili Mākaha Mākaha Valley Mākena Mānā Mokulēʻia Mōpua Mūʻolea Nāʻālehu Nāhiku Nānākuli Nānāwale Estates Nāpili-Honokōwai Nīnole Nīnole ʻŌmaʻo ʻŌmaʻopio ʻŌʻōkala Pāʻauhau Pāhala Pāhoa Pāʻia Pākalā Village Pālehua Pāpā Bay Estates Pāpaʻaloa Pāpaʻikou Poʻipū Puaʻākala Pūʻālaʻa Puakō Pūkoʻo Pūlehu Pūpūkea Puʻunēnē Wahiawā Wahīlauhue Waikāne Waikapū Waimānalo Waimānalo Beach Waiʻōhinu Waipāhoehoe Welokā Louisiana Pointe à la Hache West Pointe à la Hache Minnesota Arnesén Lindström New Mexico Cañada de los Alamos Cañon Cañon Cañoncito Cañoncito Cañoncito Cañoncito Cañones Doña Ana Española Lower Cañones Peña Blanca Peñasco Peñasco Blanco Piñon Señorito Puerto Rico Añasco Bayamón Canóvanas Cataño Comerío Guánica Juana Díaz Las Marías Loíza Manatí Mayagüez Peñuelas Rincón Río Grande San Germán San Sebastián Cañabón Castañer Río Piedras Texas César Chávez La Peñusca Lopeño Salineño Salineño North `; // 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