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String.fromCodePoint()

main Documentación oficial Licencia CC-BY-SA-2.5Descargado el 2026-08-02

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The String.fromCodePoint() static method returns a string created from the specified sequence of code points.

{{InteractiveExample("JavaScript Demo: String.fromCodePoint()", "shorter")}}

```js interactive-example console.log(String.fromCodePoint(9731, 9733, 9842, 0x2f804)); // Expected output: "☃★♲你"

## Syntax

```js-nolint
String.fromCodePoint()
String.fromCodePoint(num1)
String.fromCodePoint(num1, num2)
String.fromCodePoint(num1, num2, /* …, */ numN)

Parameters#

  • num1, …, numN
  • : An integer between 0 and 0x10FFFF (inclusive) representing a Unicode code point.

Return value#

A string created by using the specified sequence of code points.

Exceptions#

  • {{jsxref("RangeError")}}
  • : Thrown if numN is not an integer, is less than 0, or is greater than 0x10FFFF after being converted to a number.

Description#

Because fromCodePoint() is a static method of String, you always use it as String.fromCodePoint(), rather than as a method of a String value you created.

Unicode code points range from 0 to 1114111 (0x10FFFF). In UTF-16, each string index is a code unit with value 0 – 65535. Higher code points are represented by a pair of 16-bit surrogate pseudo-characters. Therefore, fromCodePoint() may return a string whose length (in UTF-16 code units) is larger than the number of arguments passed. For information on Unicode, see UTF-16 characters, Unicode code points, and grapheme clusters.

Examples#

Using fromCodePoint()#

Valid input:

String.fromCodePoint(42); // "*"
String.fromCodePoint(65, 90); // "AZ"
String.fromCodePoint(0x404); // "\u0404" === "Є"
String.fromCodePoint(0x2f804); // "\uD87E\uDC04"
String.fromCodePoint(194564); // "\uD87E\uDC04"
String.fromCodePoint(0x1d306, 0x61, 0x1d307); // "\uD834\uDF06a\uD834\uDF07"

Invalid input:

String.fromCodePoint("_"); // RangeError
String.fromCodePoint(Infinity); // RangeError
String.fromCodePoint(-1); // RangeError
String.fromCodePoint(3.14); // RangeError
String.fromCodePoint(3e-2); // RangeError
String.fromCodePoint(NaN); // RangeError

Compared to fromCharCode()#

{{jsxref("String.fromCharCode()")}} cannot return supplementary characters (i.e., code points 0x010000 – 0x10FFFF) by specifying their code point. Instead, it requires the UTF-16 surrogate pair in order to return a supplementary character:

String.fromCharCode(0xd83c, 0xdf03); // Code Point U+1F303 "Night with
String.fromCharCode(55356, 57091); // Stars" === "\uD83C\uDF03"

String.fromCodePoint(), on the other hand, can return 4-byte supplementary characters, as well as the more common 2-byte BMP characters, by specifying their code point (which is equivalent to the UTF-32 code unit):

String.fromCodePoint(0x1f303); // or 127747 in decimal

Specifications#

{{Specifications}}

Browser compatibility#

{{Compat}}

See also#