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"
"
gm

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 = "gclid=([a-zA-Z][^&#;%\\n]*)"; final String string = "__cfduid=d118f225fac35345d9e1d87e533b596ec1574680126; gclid=EAIaIQobChMIhNSMxZyF5gIVjMjeCh3V2A-pEAAYASABEgJQBPD_BwE; full_path=https://google.com/free-test/windows/; country_code=OM; clid=06a98eb3-177a-4692-8a15-04cb4c084c1c; ct_t=1574680122; ct_tid=1574680122; _ga=GA1.2.575812751.1574680122; _gid=GA1.2.560773616.1574680122; _gac_UA-138885843-1=1.1574680161.EAIaIQobChMIhNSMxZyF5gIVjMjeCh3V2A-pEAAYASABEgJQBPD_BwE; _gat=1; _gcl_aw=GCL.1574680123.EAIaIQobChMIhNSMxZyF5gIVjMjeCh3V2A-pEAAYASABEgJQBPD_BwE; _gcl_au=1.1.1227740955.1574680123; sessionid=yr0pycyfhjh90vauf0z8yw4kxno5rom0; u_id=22b5d5e0-d2b5-4a4a-ad6f-128008b4b466; _gat_UA-138885843-1=1\n" + "...\n" + "__cfduid=de7d3a7e772a62b171f445ce489bc5f791574680110; gclid=CjwKCAiAlO7uBRANEiwA_vXQ-4dP3_zZJmNXCm-P2acHITBe1XbZZZmQIGKcrL9EaoP4r9CaYEQbPxoC1uQQAvD_BwE; full_path=https://google.com/au/free-test/; country_code=AU; ct_tid=1574680121; _ga=GA1.2.476582918.1574680125; _gid=GA1.2.1129397609.1574680125; _gat=1; _gcl_au=1.1.356653701.1574680128; _gat_UA-138885843-1=1; clid=3d0b5be5-8b7b-4094-ba47-879252a59a7a; ct_t=1574680159; _gcl_aw=GCL.1574680162.CjwKCAiAlO7uBRANEiwA_vXQ-4dP3_zZJmNXCm-P2acHITBe1XbZZZmQIGKcrL9EaoP4r9CaYEQbPxoC1uQQAvD_BwE; _gac_UA-138885843-1=1.1574680169.CjwKCAiAlO7uBRANEiwA_vXQ-4dP3_zZJmNXCm-P2acHITBe1XbZZZmQIGKcrL9EaoP4r9CaYEQbPxoC1uQQAvD_BwE\n" + "__cfduid=d3b31d4cba74d440bf60e238a62bf46a51574680162; gclid=CjwKCAiAlO7uBRANEiwA_vXQ-yQeCe4-vuWQiZapqU7H5-YODheBwQf2Ra0c8CZwjf1ZGSqkw1KKXxoCeYMQAvD_BwE; full_path=https://google.com/au/best-test/; country_code=AU; clid=4e65772c-5da2-471a-86dd-240a34fd36ac; ct_t=1574680164; ct_tid=1574680164; _ga=GA1.2.242059245.1574680165; _gid=GA1.2.1757216414.1574680165; _gac_UA-138885843-1=1.1574680165.CjwKCAiAlO7uBRANEiwA_vXQ-yQeCe4-vuWQiZapqU7H5-YODheBwQf2Ra0c8CZwjf1ZGSqkw1KKXxoCeYMQAvD_BwE; _gat=1; _gcl_aw=GCL.1574680165.CjwKCAiAlO7uBRANEiwA_vXQ-yQeCe4-vuWQiZapqU7H5-YODheBwQf2Ra0c8CZwjf1ZGSqkw1KKXxoCeYMQAvD_BwE; _gcl_au=1.1.1892979809.1574680165\n" + "__cfduid=d054c8a93d4874e31aef9f2966829fefc1574680166; gclid=CjwKCAiAlO7uBRANEiwA_vXQ--5YOAD-mFNQFuM0dbd7lHsRBZSfOvhQynhZMhNHkEX-m7gosL23ABoCyS4QAvD_BwE; full_path=https://google.com/au/free-test/; country_code=AU; clid=726ebc25-95b9-4507-b29d-998ab54a9eeb; ct_t=1574680164; ct_tid=1574680164; _ga=GA1.2.1271977185.1574680165; _gid=GA1.2.506750010.1574680165; _gac_UA-138885843-1=1.1574680165.CjwKCAiAlO7uBRANEiwA_vXQ--5YOAD-mFNQFuM0dbd7lHsRBZSfOvhQynhZMhNHkEX-m7gosL23ABoCyS4QAvD_BwE; _gat=1; _gcl_aw=GCL.1574680165.CjwKCAiAlO7uBRANEiwA_vXQ--5YOAD-mFNQFuM0dbd7lHsRBZSfOvhQynhZMhNHkEX-m7gosL23ABoCyS4QAvD_BwE; _gcl_au=1.1.24394228.1574680165\n" + "__cfduid=d27ba2095c6b6ac5fb6108343075969f11574679826; full_path=https://google.com/reviews/testtest/; country_code=VN; ct_tid=1574679826; _ga=GA1.2.2008368313.1574679827; _gid=GA1.2.1231813533.1574679827; _gcl_au=1.1.299737663.1574679827; sessionid=dqwf1zmqdjkv9tdqi1cotr6m2judep2p; u_id=a71d0a87-b93d-4626-8f51-bcc0550dbbee; gclid=EAIaIQobChMI-ZOE3ZyF5gIVy2ArCh37VAdGEAEYASAAEgLCaPD_BwE; clid=aeb5b4d0-400b-47ee-b916-69a7b03544aa; ct_t=1574680166; _gac_UA-138885843-1=1.1574680167.EAIaIQobChMI-ZOE3ZyF5gIVy2ArCh37VAdGEAEYASAAEgLCaPD_BwE; _gat=1; _gcl_aw=GCL.1574680167.EAIaIQobChMI-ZOE3ZyF5gIVy2ArCh37VAdGEAEYASAAEgLCaPD_BwE"; final Pattern pattern = Pattern.compile(regex, 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