arguments.length

The arguments.length property contains the number of arguments passed to the function.

Description

The arguments.length property provides the number of arguments actually passed to a function. This can be more or less than the defined parameter's count (see Function.length).

Examples

Using arguments.length

In this example we define a function that can add two or more numbers together.

function adder(base /*, n2, ... */) {
  base = Number(base);
  for (var i = 1; i < arguments.length; i++) {
    base += Number(arguments[i]);
  }
  return base;
}

Note: Note the difference between Function.length and arguments.length

Specifications

Browser compatibility

Desktop Mobile
Chrome Edge Firefox Internet Explorer Opera Safari WebView Android Chrome Android Firefox for Android Opera Android Safari on IOS Samsung Internet
length
1
12
1
4
4
1
1
18
4
10.1
1
1.0

See also

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https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Functions/arguments/length