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

/
/
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 = "\\{\\%\\s(trans with \\{.*\\}|trans|transchoice)\\s\\%\\}(.*)\\{\\%\\s(endtrans|endtranschoice)\\s\\%\\}"; final String string = "{% if estimate_delivery.text is not empty %}\n" + " {% if estimate_delivery.day and estimate_delivery.month %}\n" + " <strong>{% trans %}Order delivery estimation:{% endtrans %}</strong>\n" + " {{ estimate_delivery.day }} {{ estimate_delivery.month | trans }} {{ estimate_delivery.text }} {{ estimate_delivery.interval }}\n" + " {% elseif estimate_delivery.text %}\n" + " <strong>{% trans %}Order delivery estimation:{% endtrans %}</strong>\n" + " {{ estimate_delivery.text }} {{ estimate_delivery.interval }}\n" + " {% endif %}\n" + " <div class=\"emg-clear\"></div>\n" + "{% else %}\n" + " {% trans %}No delivery estimate data available.{% endtrans %}\n" + "{% endif %}\n" + "<div id=\"sameDay\">\n" + " <input id=\"same-day-chk\" type=\"checkbox\" name=\"shipping[courier][same_day]\" value=\"1\" class=\"gui-checkbox\" {% if same_day.show == false %}disabled=\"disabled\"{% endif %}>\n" + " <label for=\"same-day-chk\" class=\"gui-label\">{% trans with {'%price%': money_format(same_day.price)} %}I want my order shipped today ( only %price%){% endtrans %}</label>\n\n" + " {% if same_day.show != false %}\n" + " <strong>{{ same_day.info.message|raw }} <a href=\"#\" data-count=\"{{ same_day.products|length }}\" id=\"sameDayDelivery\">( {{ same_day.products|length }} items )</a></strong>\n" + " <div id=\"sameDayDelivery-emgBubble\" class=\"emg-bubble\">\n" + " {% for product in same_day.products %}\n" + " <div class=\"emg-left\">\n" + " <img src=\"{{ product.image }}\" alt=\"\" />\n" + " </div>\n" + " <div class=\"emg-right\">\n" + " {{ product.name }}\n" + " </div>\n" + " <div class=\"emg-clear\"></div>\n" + " {% endfor %}\n\n" + " <div class=\"button\">\n" + " <i class=\"icon-i27-round-close\"></i>\n" + " </div>\n" + " <div class=\"emg-clear\"></div>\n" + " </div>\n" + " {% endif %}\n" + "</div>\n"; 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