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

@"""
"""
gim

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 = "(\\[|)\\{\\n(?<tab> )\"id\": \"[0-9]*\",\\n\\<tab>\"type\": [0-9],\\n\\<tab>\"content\": \"[^\"]*\",\\n\\<tab>\"channel_id\": \"[0-9]*\",\\n\\<tab>\"author\": \\{\\n(?<dtab> )\"id\": \"[^\"]*\",\\n\\<dtab>\"username\": \"[^\"]*\",\\n\\<dtab>\"avatar\": \"[^\"]*\",\\n\\<dtab>\"discriminator\": \"([0-9]{4}|[0-9])\",\\n\\<dtab>\"public_flags\": [0-9]*,\\n\\<dtab>\"flags\": [0-9]*,\\n\\<dtab>\"banner\": (null|\"[0-9]*\"),\\n\\<dtab>\"accent_color\": (null|\"[^\"]*\"),\\n\\<dtab>\"global_name\": \"[^\"]*\",\\n\\<dtab>\"avatar_decoration_data\": (null|\"[^\"]*\"),\\n\\<dtab>\"banner_color\": (null|\"[^\"]*\")\\n\\<tab>\\},\\n\\<tab>\"attachments\": \\[[^\\]]*\\],\\n\\<tab>\"embeds\": \\[[^\\]]*],\\n\\<tab>\"mentions\": \\[[^\\]]*],\\n\\<tab>\"mention_roles\": \\[[^\\]]*\\],\\n\\<tab>\"pinned\": (true:|false),\\n\\<tab>\"mention_everyone\": (true|false),\\n\\<tab>\"tts\": (true:|false),\\n\\<tab>\"timestamp\": \"[0-9]{4}-[0-9]{2}-[0-9]{2}T[0-9]{2}:[0-9]{2}:[0-9]{2}.[0-9]{6}\\+[0-9]{2}:[0-9]{2}\",\\n\\<tab>\"edited_timestamp\": (null|\"[0-9]{4}-[0-9]{2}-[0-9]{2}T[0-9]{2}:[0-9]{2}:[0-9]{2}.[0-9]{6}\\+[0-9]{2}:[0-9]{2}\"),\\n\\<tab>\"flags\": [0-9]*,\\n\\<tab>\"components\": \\[[^\\]]*]\\n\\}(\\]|\\,|)"; final String string = "{\n" + " \"id\": \"1145344233713188874\",\n" + " \"type\": 0,\n" + " \"content\": \"913 - this icecream good\",\n" + " \"channel_id\": \"1124414874454339715\",\n" + " \"author\": {\n" + " \"id\": \"746383273621717104\",\n" + " \"username\": \"kalote.\",\n" + " \"avatar\": \"95b9bdc7aa5784a2354e2ec5256ae736\",\n" + " \"discriminator\": \"0\",\n" + " \"public_flags\": 128,\n" + " \"flags\": 128,\n" + " \"banner\": null,\n" + " \"accent_color\": null,\n" + " \"global_name\": \"Carrot :3\",\n" + " \"avatar_decoration_data\": null,\n" + " \"banner_color\": null\n" + " },\n" + " \"attachments\": [],\n" + " \"embeds\": [],\n" + " \"mentions\": [],\n" + " \"mention_roles\": [],\n" + " \"pinned\": false,\n" + " \"mention_everyone\": false,\n" + " \"tts\": false,\n" + " \"timestamp\": \"2023-08-27T13:09:04.784000+00:00\",\n" + " \"edited_timestamp\": null,\n" + " \"flags\": 0,\n" + " \"components\": []\n" + "},"; final Pattern pattern = Pattern.compile(regex, Pattern.CASE_INSENSITIVE | 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