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

/
/
gi

Test String

Code Generator

Language

Generated Code

import java.util.regex.Matcher; import java.util.regex.Pattern; public class Example { public static void main(String[] args) { final String regex = "((?:\\b(I+|1st|2nd|3rd|First|Second|Third|1|2|3))?( )?\\b(Gen|Ge|Gn|Exo|Ex|Exod|Lev|Le|Lv|Num|Nu|Nm|Nb|Deut|Dt|Josh|Jos|Jsh|Judg|Jdg|Jg|Jdgs|Rth|Ru|Sam|Samuel|Kings|Kgs|Kin|Chron|Chronicles|Ezra|Ezr|Neh|Ne|Esth|Es|Job|Job|Jb|Pslm|Ps|Psalms|Psa|Psm|Pss|Prov|Pr|Prv|Eccles|Ec|Song|So|Canticles|Song of Songs|SOS|Isa|Is|Jer|Je|Jr|Lam|La|Ezek|Eze|Ezk|Dan|Da|Dn|Hos|Ho|Joel|Joe|Jl|Amos|Am|Obad|Ob|Jnh|Jon|Micah|Mic|Nah|Na|Hab|Zeph|Zep|Zp|Haggai|Hag|Hg|Zech|Zec|Zc|Mal|Mal|Ml|Matt|Mt|Mrk|Mk|Mr|Luk|Lk|John|Jn|Jhn|Acts|Ac|Rom|Ro|Rm|Co|Cor|Corinthians|Gal|Ga|Ephes|Eph|Phil|Php|Col|Col|Th|Thes|Thess|Thessalonians|Ti|Tim|Timothy|Titus|Tit|Philem|Phm|Hebrews|Heb|James|Jas|Jm|Pe|Pet|Pt|Peter|Jn|Jo|Joh|Jhn|John|Jude|Jud|Rev|The Revelation|Genesis|Exodus|Leviticus|Numbers|Deuteronomy|Joshua|Judges|Ruth|Samuel|Kings|Chronicles|Ezra|Nehemiah|Esther|Job|Psalms|Psalm|Proverbs|Ecclesiastes|Song of Solomon|Isaiah|Jeremiah|Lamentations|Ezekiel|Daniel|Hosea|Joel|Amos|Obadiah|Jonah|Micah|Nahum|Habakkuk|Zephaniah|Haggai|Zechariah|Malachi|Matthew|Mark|Luke|John|Acts|Romans|Corinthians|Galatians|Ephesians|Philippians|Colossians|Thessalonians|Timothy|Titus|Philemon|Hebrews|James|Peter|John|Jude|Revelation))\\b(([ .)\\n|])([^a-zA-Z]?))([\\d])?([:\\d])?([:\\d])?"; final String string = "Today’s readings.. (Numbers 5), (Proverbs 2), (Luke 16)\n\n" + "Jude some more text\n" + "1 Peter 1:2\n" + "James \n" + "rev 3:2\n" + "March 14"; final Pattern pattern = Pattern.compile(regex, Pattern.CASE_INSENSITIVE); 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