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 = "jjj[0-9]+(\\.[0-9][0-9]?)"; final String string = "03-Feb-2021\n" + "Mr./Ms. JOHN THACHIL\n" + "MADHURA SURAKSHA APARTMENT\n" + "S6 2ND FLOOR\n" + "JP NAGAR 5TH PHASE\n" + "BANGALORE 560078\n" + "Dear Customer, \n" + "Subject: EasyEMI on your HDFC Bank Credit Card Number:jjj552260XXXXXX0961\n" + "We are pleased to grant you the EasyEMI payment facility as per the details stated below. The\n" + "transaction amount has been converted into EasyEMI as per your request\n" + "EasyEMI Loan no. 0000000000065214714\n" + "Unsecured Loan Type EasyEMI\n" + "Amount Rs.3399.00\n" + "Tenure 3 Months\n" + "EasyEMI Fixed Finance Charges on Reducing Balance 1.25% p.m.\n" + "EMI Amount Rs.1161.44(Excluding GST)*\n" + "Merchant Name \n" + "Processing Fee Rs.199.00\n" + "*GST at 18% will be charged on the following and are subjected to change as per Govt.Announcement:\n" + "1.EasyEMI Finance Charges Component on the EMI amount on a monthly basis\n" + "2.Processing fee, if any\n" + "3.Pre-closure charges, if any\n" + "Please refer to the enclosed amortization schedule for EMI details\n" + "For the first EMI, the interest will be calculated from the loan booking date till the payment due date. This\n" + "is effective only for loans booked from Feb 2019 onwards.In case you require any further assistance , pls\n" + "contact Phone Banking within 7 days of receiving this letter\n" + "EasyEMI transactions are not eligible for Reward Points.This EasyEMI can be pre-closed anytime during the\n" + "tenure. In case of pre-closure of the EasyEMI facility, there will be no Penalty levied currently. As the pre-closure\n" + "charge is subjected to change, we request you to get in touch with your nearest call centre for the applicable\n" + "charge, if any, if you decide to pre-close the EasyEMI. Partial pre-payment or partial closure is not permitted on\n" + "this loan\n" + "Additional Finance Charges if any on the principal outstanding from last statement date till date of loan pre-\n" + "closure need to be paid by customer.\n" + "Please also note that the above mentioned EMI amounts will be included to your monthly HDFC Bank Credit Card\n" + "statements and will be payable as part of the Minimum Amount Due.\n" + "If your HDFC Bank Card gets closed before all the installments have been charged, the loan outstanding will get\n" + "debited to your card account and you’re expected to pay the amount in full. In case of default in payment of credit\n" + "card dues or EMIs by the due dates, your card account is liable to be suspended and could further be terminated.\n" + "The terms and conditions contained in the Cardmember Agreement apply over and above the terms and\n" + "conditions for this loan. In case you do not agree to any of the details above, or require any further assistance,\n" + "please contact the nearest customer service call centre at the numbers provided below, within 7 days of receiving\n" + "this letter.\n" + "Enclosed Amortization schedule of Loan Number 0000000000065214714 for Loan Amount Rs.3399.00\n" + "(*GST extra @18% on Interest Component)\n" + "NojjjNo\n" + "EasyEMIjjjEasyEMI\n" + "StatementjjjPrincipaljjjEMIjjjBalancejjjStatementjjjPrincipaljjjEMIjjjBalance\n" + "FinancejjjFinance\n" + "DatejjjAmountjjjAmountjjjDatejjjAmountjjjAmount\n" + "ChargesjjjCharges\n" + "onjjjon\n" + "ReducingjjjReducing\n" + "BalancejjjBalance\n" + "21-02-2021jjj21-04-2021\n" + "1jjj1118.96jjj70.88jjj1189.84jjj2280.04jjj3jjj1147.10jjj14.33jjj1161.43jjj0.00\n" + "21-03-2021\n" + "2jjj1132.94jjj28.50jjj1161.44jjj1147.10\n" + "This is a computer generated letter and does not require a signature."; 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