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

r"
"
g

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 = "var data\\s*=\\s*([^;]*\\});"; final String string = "<script type=\"text/javascript\">\n" + "P.when('A').register(\"ImageBlockATF\", function(A){\n" + " var data = {\n" + " 'colorImages': { 'initial': [{\"hiRes\":\"https://images-na.ssl-images-amazon.com/images/I/81Oo79kGp2L._SL1500_.jpg\",\"thumb\":\"https://images-na.ssl-images-amazon.com/images/I/41SnVVzKChL._SS40_.jpg\",\"large\":\"https://images-na.ssl-images-amazon.com/images/I/41SnVVzKChL.jpg\",\"main\":{\"https://images-na.ssl-images-amazon.com/images/I/81Oo79kGp2L._SY355_.jpg\":[355,270],\"https://images-na.ssl-images-amazon.com/images/I/81Oo79kGp2L._SY450_.jpg\":[450,342],\"https://images-na.ssl-images-amazon.com/images/I/81Oo79kGp2L._SY550_.jpg\":[550,419],\"https://images-na.ssl-images-amazon.com/images/I/81Oo79kGp2L._SY606_.jpg\":[606,461],\"https://images-na.ssl-images-amazon.com/images/I/81Oo79kGp2L._SY679_.jpg\":[679,517]},\"variant\":\"MAIN\",\"lowRes\":null},{\"hiRes\":\"https://images-na.ssl-images-amazon.com/images/I/81%2BGc-r4gLL._SL1500_.jpg\",\"thumb\":\"https://images-na.ssl-images-amazon.com/images/I/416rXB0xcmL._SS40_.jpg\",\"large\":\"https://images-na.ssl-images-amazon.com/images/I/416rXB0xcmL.jpg\",\"main\":{\"https://images-na.ssl-images-amazon.com/images/I/81%2BGc-r4gLL._SY355_.jpg\":[355,276],\"https://images-na.ssl-images-amazon.com/images/I/81%2BGc-r4gLL._SY450_.jpg\":[450,349],\"https://images-na.ssl-images-amazon.com/images/I/81%2BGc-r4gLL._SX425_.jpg\":[547,425],\"https://images-na.ssl-images-amazon.com/images/I/81%2BGc-r4gLL._SX466_.jpg\":[600,466],\"https://images-na.ssl-images-amazon.com/images/I/81%2BGc-r4gLL._SX522_.jpg\":[672,522]},\"variant\":\"PT01\",\"lowRes\":null},{\"hiRes\":\"https://images-na.ssl-images-amazon.com/images/I/817slrgsGbL._SL1500_.jpg\",\"thumb\":\"https://images-na.ssl-images-amazon.com/images/I/51gQxeLTYhL._SS40_.jpg\",\"large\":\"https://images-na.ssl-images-amazon.com/images/I/51gQxeLTYhL.jpg\",\"main\":{\"https://images-na.ssl-images-amazon.com/images/I/817slrgsGbL._SX355_.jpg\":[251,355],\"https://images-na.ssl-images-amazon.com/images/I/817slrgsGbL._SX450_.jpg\":[318,450],\"https://images-na.ssl-images-amazon.com/images/I/817slrgsGbL._SX425_.jpg\":[300,425],\"https://images-na.ssl-images-amazon.com/images/I/817slrgsGbL._SX466_.jpg\":[329,466],\"https://images-na.ssl-images-amazon.com/images/I/817slrgsGbL._SX522_.jpg\":[369,522]},\"variant\":\"PT02\",\"lowRes\":null},{\"hiRes\":\"https://images-na.ssl-images-amazon.com/images/I/71r3nXKZBmL._SL1500_.jpg\",\"thumb\":\"https://images-na.ssl-images-amazon.com/images/I/41d9m8J4MbL._SS40_.jpg\",\"large\":\"https://images-na.ssl-images-amazon.com/images/I/41d9m8J4MbL.jpg\",\"main\":{\"https://images-na.ssl-images-amazon.com/images/I/71r3nXKZBmL._SX355_.jpg\":[142,355],\"https://images-na.ssl-images-amazon.com/images/I/71r3nXKZBmL._SX450_.jpg\":[180,450],\"https://images-na.ssl-images-amazon.com/images/I/71r3nXKZBmL._SX425_.jpg\":[170,425],\"https://images-na.ssl-images-amazon.com/images/I/71r3nXKZBmL._SX466_.jpg\":[187,466],\"https://images-na.ssl-images-amazon.com/images/I/71r3nXKZBmL._SX522_.jpg\":[209,522]},\"variant\":\"PT03\",\"lowRes\":null},{\"hiRes\":\"https://images-na.ssl-images-amazon.com/images/I/81Uys4ccU4L._SL1500_.jpg\",\"thumb\":\"https://images-na.ssl-images-amazon.com/images/I/41zh%2BCGamHL._SS40_.jpg\",\"large\":\"https://images-na.ssl-images-amazon.com/images/I/41zh%2BCGamHL.jpg\",\"main\":{\"https://images-na.ssl-images-amazon.com/images/I/81Uys4ccU4L._SY355_.jpg\":[355,260],\"https://images-na.ssl-images-amazon.com/images/I/81Uys4ccU4L._SY450_.jpg\":[450,330],\"https://images-na.ssl-images-amazon.com/images/I/81Uys4ccU4L._SY550_.jpg\":[550,403],\"https://images-na.ssl-images-amazon.com/images/I/81Uys4ccU4L._SY606_.jpg\":[606,444],\"https://images-na.ssl-images-amazon.com/images/I/81Uys4ccU4L._SY679_.jpg\":[679,498]},\"variant\":\"PT04\",\"lowRes\":null},{\"hiRes\":\"https://images-na.ssl-images-amazon.com/images/I/8179KoLoyGL._SL1500_.jpg\",\"thumb\":\"https://images-na.ssl-images-amazon.com/images/I/41sMHp-WegL._SS40_.jpg\",\"large\":\"https://images-na.ssl-images-amazon.com/images/I/41sMHp-WegL.jpg\",\"main\":{\"https://images-na.ssl-images-amazon.com/images/I/8179KoLoyGL._SY355_.jpg\":[355,258],\"https://images-na.ssl-images-amazon.com/images/I/8179KoLoyGL._SY450_.jpg\":[450,327],\"https://images-na.ssl-images-amazon.com/images/I/8179KoLoyGL._SY550_.jpg\":[550,400],\"https://images-na.ssl-images-amazon.com/images/I/8179KoLoyGL._SY606_.jpg\":[606,441],\"https://images-na.ssl-images-amazon.com/images/I/8179KoLoyGL._SY679_.jpg\":[679,494]},\"variant\":\"PT05\",\"lowRes\":null},{\"hiRes\":\"https://images-na.ssl-images-amazon.com/images/I/71Sw2wrvy6L._SL1364_.jpg\",\"thumb\":\"https://images-na.ssl-images-amazon.com/images/I/416TFrjOFlL._SS40_.jpg\",\"large\":\"https://images-na.ssl-images-amazon.com/images/I/416TFrjOFlL.jpg\",\"main\":{\"https://images-na.ssl-images-amazon.com/images/I/71Sw2wrvy6L._SX355_.jpg\":[231,355],\"https://images-na.ssl-images-amazon.com/images/I/71Sw2wrvy6L._SX450_.jpg\":[293,450],\"https://images-na.ssl-images-amazon.com/images/I/71Sw2wrvy6L._SX425_.jpg\":[277,425],\"https://images-na.ssl-images-amazon.com/images/I/71Sw2wrvy6L._SX466_.jpg\":[304,466],\"https://images-na.ssl-images-amazon.com/images/I/71Sw2wrvy6L._SX522_.jpg\":[340,522]},\"variant\":\"PT06\",\"lowRes\":null},{\"hiRes\":\"https://images-na.ssl-images-amazon.com/images/I/61GKBhtPKPL._SL1341_.jpg\",\"thumb\":\"https://images-na.ssl-images-amazon.com/images/I/41%2BNMI0l9yL._SS40_.jpg\",\"large\":\"https://images-na.ssl-images-amazon.com/images/I/41%2BNMI0l9yL.jpg\",\"main\":{\"https://images-na.ssl-images-amazon.com/images/I/61GKBhtPKPL._SX355_.jpg\":[190,355],\"https://images-na.ssl-images-amazon.com/images/I/61GKBhtPKPL._SX450_.jpg\":[240,450],\"https://images-na.ssl-images-amazon.com/images/I/61GKBhtPKPL._SX425_.jpg\":[227,425],\"https://images-na.ssl-images-amazon.com/images/I/61GKBhtPKPL._SX466_.jpg\":[249,466],\"https://images-na.ssl-images-amazon.com/images/I/61GKBhtPKPL._SX522_.jpg\":[279,522]},\"variant\":\"PT07\",\"lowRes\":null},{\"hiRes\":null,\"thumb\":\"https://images-na.ssl-images-amazon.com/images/I/41ziorm06nL._SS40_.jpg\",\"large\":\"https://images-na.ssl-images-amazon.com/images/I/41ziorm06nL.jpg\",\"main\":{\"https://images-na.ssl-images-amazon.com/images/I/41ziorm06nL._SY355_.jpg\":[355,266],\"https://images-na.ssl-images-amazon.com/images/I/41ziorm06nL._SY450_.jpg\":[450,338],\"https://images-na.ssl-images-amazon.com/images/I/41ziorm06nL.jpg\":[500,375]},\"variant\":\"AW01\",\"lowRes\":null},{\"hiRes\":null,\"thumb\":\"https://images-na.ssl-images-amazon.com/images/I/41lZ6jtPe%2BL._SS40_.jpg\",\"large\":\"https://images-na.ssl-images-amazon.com/images/I/41lZ6jtPe%2BL.jpg\",\"main\":{\"https://images-na.ssl-images-amazon.com/images/I/41lZ6jtPe%2BL._SY355_.jpg\":[355,266],\"https://images-na.ssl-images-amazon.com/images/I/41lZ6jtPe%2BL._SY450_.jpg\":[450,338],\"https://images-na.ssl-images-amazon.com/images/I/41lZ6jtPe%2BL.jpg\":[500,375]},\"variant\":\"AW02\",\"lowRes\":null},{\"hiRes\":null,\"thumb\":\"https://images-na.ssl-images-amazon.com/images/I/51JqQcNGjUL._SS40_.jpg\",\"large\":\"https://images-na.ssl-images-amazon.com/images/I/51JqQcNGjUL.jpg\",\"main\":{\"https://images-na.ssl-images-amazon.com/images/I/51JqQcNGjUL._SY355_.jpg\":[355,355],\"https://images-na.ssl-images-amazon.com/images/I/51JqQcNGjUL._SY450_.jpg\":[450,450],\"https://images-na.ssl-images-amazon.com/images/I/51JqQcNGjUL._SX425_.jpg\":[425,425],\"https://images-na.ssl-images-amazon.com/images/I/51JqQcNGjUL._SX466_.jpg\":[466,466],\"https://images-na.ssl-images-amazon.com/images/I/51JqQcNGjUL.jpg\":[500,500]},\"variant\":\"AW03\",\"lowRes\":null}]},\n" + " 'colorToAsin': {'initial': {}},\n" + " 'holderRatio': 1.0,\n" + " 'holderMaxHeight': 700,\n" + " 'heroImage': {'initial': []},\n" + " 'weblabs' : {}\n" + " };\n" + " A.trigger('P.AboveTheFold'); // trigger ATF event.\n" + " return data;\n" + "});\n" + "</script>"; final Pattern pattern = Pattern.compile(regex); 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