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 single character of: a, b, c or d
    [[ab][cd]]
  • 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]
  • Character class intersection
    [\w&&[^\d]]
  • 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

"
"

Test String

Code Generator

Language

Generated Code

const regex = new RegExp('\\"app\\":\\s\\{((.|\\n)*)\\"local\\"', '') const str = `{ "app": { "local": "True", "dependency_env": "dev" }, "engine": { "disable_jwt_check": "true", "jwt_private_key": "sph59tZqVrjqz3BiVUnXvKRgd6BxDkN2E+TAjy96wfASO4/5DGJIQlZvnNSt4H7wKLQ0b1J5AdNJ7315B9My6w==", "jwt_issuer": "https://hbgpmwapi-dev.kantar.com" }, "azure": { "app_id": "efe4d19e-880e-480e-8e0c-f86c9fd5872c", "app_key": "b1e5em8uILeqAI.0jt=zg[mJHSaaHKz:", "env": "dev", "storage_key": "pKhqboH2XDRpYNLco4vyPapHNd7Ao/BO28yFBD0ooSSn/828NLMfKkkzdrqUyeeA2312Y9xAix1T/YdAHkbZCw==", "storage_container": "marketingpressure", "storage_endpoint": "https://hbgenginestorage.blob.core.windows.net" }, "URL": { "main": "http://localhost:3838" } }`; // Reset `lastIndex` if this regex is defined globally // regex.lastIndex = 0; let m; if ((m = regex.exec(str)) !== null) { // The result can be accessed through the `m`-variable. m.forEach((match, groupIndex) => { console.log(`Found match, group ${groupIndex}: ${match}`); }); }

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 JavaScript, please visit: https://developer.mozilla.org/en/docs/Web/JavaScript/Guide/Regular_Expressions