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

Generated Code

import java.util.regex.Matcher; import java.util.regex.Pattern; public class Example { public static void main(String[] args) { final String regex = "^[-ʻ'`a-zġūĀñēöåàíáüóéōāī ]+$"; final String string = "https://en.wikipedia.org/wiki/List_of_U.S._cities_with_diacritics\n\n" + "Alaska\n\n" + "Alaska\n" + "Utqiaġvik\n\n\n" + "American Samoa\n" + "Āfono\n" + "Ālega\n" + "'Āmanave\n" + "Āmouli\n" + "Aūa\n" + "Fagasā\n" + "Faleāsao\n" + "Lumā\n" + "Tāfuna\n\n\n" + "California\n" + "La Cañada Flintridge\n" + "Piñon Hills\n" + "San José\n\n\n" + "Colorado\n" + "Cañon\n" + "Cañon City\n" + "Piñon\n" + "Piñon\n" + "Piñon Acres\n\n\n" + "Guam\n" + "Hagåtña\n" + "Hagåtña Heights\n\n\n" + "Hawaii\n" + "ʻĀhuimanu\n" + "ʻ````Āinaloa\n" + "Hanapēpē\n" + "Haʻikū-Pauwela\n" + "Hālawa\n" + "Hāliʻimaile\n" + "Hāmoa\n" + "Hāna\n" + "Hāʻōʻū\n" + "Hāwī\n" + "Hīlea\n" + "Hōlualoa\n" + "Hōnaunau-Nāpōʻopoʻo\n" + "Honokōhau\n" + "Hoʻōpūloa\n" + "Kāʻanapali\n" + "Kaimū\n" + "Kākiʻo\n" + "Kalāheo\n" + "Kamalō\n" + "Kāneʻohe\n" + "Kaupō\n" + "Kaʻūpūlehu\n" + "Keālia\n" + "Kēōkea\n" + "Kēōkea\n" + "Kīhei\n" + "Kīholo\n" + "Kīlauea\n" + "Kīpahulu\n" + "Kīpū\n" + "Kōloa\n" + "Kūkaʻiau\n" + "Kūkiʻo\n" + "Lāʻie\n" + "Lānaʻi City\n" + "Laupāhoehoe\n" + "Lāwaʻi\n" + "Līhuʻe\n" + "Māʻalaea\n" + "Māʻili\n" + "Mākaha\n" + "Mākaha Valley\n" + "Mākena\n" + "Mānā\n" + "Mokulēʻia\n" + "Mōpua\n" + "Mūʻolea\n" + "Nāʻālehu\n" + "Nāhiku\n" + "Nānākuli\n" + "Nānāwale Estates\n" + "Nāpili-Honokōwai\n" + "Nīnole\n" + "Nīnole\n" + "ʻŌmaʻo\n" + "ʻŌmaʻopio\n" + "ʻŌʻōkala\n" + "Pāʻauhau\n" + "Pāhala\n" + "Pāhoa\n" + "Pāʻia\n" + "Pākalā Village\n" + "Pālehua\n" + "Pāpā Bay Estates\n" + "Pāpaʻaloa\n" + "Pāpaʻikou\n" + "Poʻipū\n" + "Puaʻākala\n" + "Pūʻālaʻa\n" + "Puakō\n" + "Pūkoʻo\n" + "Pūlehu\n" + "Pūpūkea\n" + "Puʻunēnē\n" + "Wahiawā\n" + "Wahīlauhue\n" + "Waikāne\n" + "Waikapū\n" + "Waimānalo\n" + "Waimānalo Beach\n" + "Waiʻōhinu\n" + "Waipāhoehoe\n" + "Welokā\n\n\n" + "Louisiana\n" + "Pointe à la Hache\n" + "West Pointe à la Hache\n\n\n" + "Minnesota\n" + "Arnesén\n" + "Lindström\n\n\n" + "New Mexico\n" + "Cañada de los Alamos\n" + "Cañon\n" + "Cañon\n" + "Cañoncito\n" + "Cañoncito\n" + "Cañoncito\n" + "Cañoncito\n" + "Cañones\n" + "Doña Ana\n" + "Española\n" + "Lower Cañones\n" + "Peña Blanca\n" + "Peñasco\n" + "Peñasco Blanco\n" + "Piñon\n" + "Señorito\n\n\n" + "Puerto Rico\n" + "Añasco\n" + "Bayamón\n" + "Canóvanas\n" + "Cataño\n" + "Comerío\n" + "Guánica\n" + "Juana Díaz\n" + "Las Marías\n" + "Loíza\n" + "Manatí\n" + "Mayagüez\n" + "Peñuelas\n" + "Rincón\n" + "Río Grande\n" + "San Germán\n" + "San Sebastián\n" + "Cañabón\n" + "Castañer\n" + "Río Piedras\n" + "Texas\n" + "César Chávez\n" + "La Peñusca\n" + "Lopeño\n" + "Salineño\n" + "Salineño North\n"; final Pattern pattern = Pattern.compile(regex, Pattern.CASE_INSENSITIVE | Pattern.MULTILINE); final Matcher matcher = pattern.matcher(string); while (matcher.find()) { System.out.println("Full match: " + matcher.group(0)); for (int i = 1; i <= matcher.groupCount(); i++) { System.out.println("Group " + i + ": " + matcher.group(i)); } } } }

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 Java, please visit: https://docs.oracle.com/javase/7/docs/api/java/util/regex/Pattern.html