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

const regex = /\b([KNW][A-Z]?|A[A-L])[0-9][A-Z]{1,3}\b(?:-@)?/g; // Alternative syntax using RegExp constructor // const regex = new RegExp('\\b([KNW][A-Z]?|A[A-L])[0-9][A-Z]{1,3}\\b(?:-@)?', 'g') const str = `\$pattern .= ""; //N9URK, W1AW, W1W \$pattern .= ""; //WB6NOA, AD4HZ, WA1W IW1GJR K, N, W, AA-AL, KA-KZ, NA-NZ or WA-WZ All of these returning false with RegEx.test in JavaScript: pen.js:23 JA1HOX pen.js:23 IQ6WJ pen.js:23 CE2AWW pen.js:23 SK2AT pen.js:23 IW1EVR pen.js:23 9A3LE-@ pen.js:23 EA5IGO pen.js:23 SK2AT pen.js:23 W6BOI <------- pen.js:23 IZ3ZUS pen.js:23 YO3YX pen.js:23 ON4LDP pen.js:23 BG3UPA pen.js:23 FW5JJ pen.js:23 RM4D-@ pen.js:23 RN3QTS pen.js:23 OH6PA pen.js:23 W3LPL <------- pen.js:23 SK2AT pen.js:23 K2CYS pen.js:23 EW4DW pen.js:23 EC1DJ pen.js:23 R3NA pen.js:23 JA6GGD pen.js:23 N3YZ-@ pen.js:23 K0BX pen.js:23 WA2VUY-@ pen.js:23 IZ3WXG pen.js:23 DD3EU-@ pen.js:23 UR4UWY-@ pen.js:23 ON4LDP pen.js:23 K5VJZ pen.js:23 RZ3LA-@ pen.js:23 OE9NFI pen.js:23 OH1F pen.js:23 K2CYS pen.js:23 HA0DU pen.js:23 EB8CRM pen.js:23 TA2OTT-@ pen.js:23 EA1AST pen.js:23 N0TR pen.js:23 RK6FV pen.js:23 YU7AF pen.js:23 F0FVK pen.js:23 FW5JJ pen.js:23 R2ZA-@ pen.js:23 G0LGS pen.js:23 5B4AIZ-@ pen.js:23 RZ3LA-@ 7275 N4N 2015-10-06T19:32:38 military convoy SE United States N8POG 7183 LZ130SAK 2015-10-06T19:30:04 CQ cq SES AWARD Bulgaria DL2AMM 7275 N4N 2015-10-06T19:29:03 Bankhead Convoy Host Station United States KA4WJR-@ 18163 CN8NOA 2015-10-06T19:28:22 your dear friend NORI Morocco W4QNW 14268 S79SP 2015-10-06T19:28:16 Listening up Seychelles WA3ZHG-@ 1846 HG8ITU 2015-10-06T19:27:18 CQ RTTY RTTY Hungary HA8BT 14260 W1AW 2015-10-06T19:26:06 tnx United States IW1GJR 14268 S79SP 2015-10-06T19:25:53 59 EPA by mumbers up10 Seychelles W3RJW`; // Reset `lastIndex` if this regex is defined globally // regex.lastIndex = 0; let m; while ((m = regex.exec(str)) !== null) { // This is necessary to avoid infinite loops with zero-width matches if (m.index === regex.lastIndex) { regex.lastIndex++; } // 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