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break

Baseline Widely available

This feature is well established and works across many devices and browser versions. Its been available across browsers since 2015 7.

break , switch , label , .

In this article

let i = 0;

while (i < 6) {
  if (i === 3) {
    break;
  }
  i = i + 1;
}

console.log(i);
// Expected output: 3

js
    break [label];
label Optional

. switch .

break label label . break label . label block . , loop .

i 3 while loop break , 3 * x .

js
function testBreak(x) {
  var i = 0;

  while (i &#x3C; 6) {
    if (i == 3) {
      break;
    }
    i += 1;
  }

  return i * x;
}

label break . break label . inner_block outer_block .

js
outer_block: {
  inner_block: {
    console.log("1");
    break outer_block; // inner_block outer_block  
    console.log(":-("); // 
  }
  console.log("2"); // 
}

label break break block_2 block_1 (Syntax Error) . break label .

js
block_1: {
  console.log('1');
  break block_2; // SyntaxError: label   
}

block_2: {
  console.log('2');
}

Specification
ECMAScript 2027 LanguageSpecification
# sec-break-statement

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  1. JavaScript
  2. :
  3. JavaScript
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    1. JavaScript (JS )
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  6. :
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  11. Classes
    1. constructor
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    1. Backreference: \1, \2
    2. Capturing group: (...)
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    4. Character class: [...], [^...]
    5. Character escape: \n, \u{...}
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    7. Input boundary assertion: ^, $
    8. Literal character: a, b
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    11. Modifier: (?ims-ims:...)
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    13. Named capturing group: (?<name>...)
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    60. SyntaxError: missing ) after argument list
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    62. SyntaxError: missing ] after element list
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    64. SyntaxError: missing } after property list
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    75. SyntaxError: private fields can't be deleted
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    77. SyntaxError: raw bracket is not allowed in regular expression with unicode flag
    78. SyntaxError: redeclaration of formal parameter "x"
    79. SyntaxError: reference to undeclared private field or method #x
    80. SyntaxError: rest parameter may not have a default
    81. SyntaxError: return not in function
    82. SyntaxError: setter functions must have one argument
    83. SyntaxError: string literal contains an unescaped line break
    84. SyntaxError: super() is only valid in derived class constructors
    85. SyntaxError: tagged template cannot be used with optional chain
    86. SyntaxError: Unexpected '#' used outside of class body
    87. SyntaxError: Unexpected token
    88. SyntaxError: unlabeled break must be inside loop or switch
    89. SyntaxError: unparenthesized unary expression can't appear on the left-hand side of '**'
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    92. ReferenceError: deprecated caller or arguments usage
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    99. TypeError: already executing generator
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    104. TypeError: can't convert BigInt to number
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    107. TypeError: can't delete non-configurable array element
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    109. TypeError: can't set prototype of this object
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    112. TypeError: class constructors must be invoked with 'new'
    113. TypeError: cyclic object value
    114. TypeError: derived class constructor returned invalid value x
    115. TypeError: getting private setter-only property
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    117. TypeError: invalid 'instanceof' operand 'x'
    118. TypeError: invalid Array.prototype.sort argument
    119. TypeError: invalid assignment to const "x"
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    121. TypeError: matchAll/replaceAll must be called with a global RegExp
    122. TypeError: More arguments needed
    123. TypeError: "x" has no properties
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    125. TypeError: Reduce of empty array with no initial value
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    128. TypeError: X.prototype.y called on incompatible type
    129. URIError: malformed URI sequence
    130. Warning: -file- is being assigned a //# sourceMappingURL, but already has one
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    1. JavaScript
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    3. Lexical
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    7. Trailing commas
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