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---
title: String.fromCodePoint()
slug: Web/JavaScript/Reference/Global_Objects/String/fromCodePoint
translation_of: Web/JavaScript/Reference/Global_Objects/String/fromCodePoint
original_slug: Web/JavaScript/Referencje/Obiekty/String/fromCodePoint
---
<div>{{JSRef}}</div>
<p>The static <strong><code>String.fromCodePoint()</code></strong> method returns a string created by using the specified sequence of code points.</p>
<div>{{EmbedInteractiveExample("pages/js/string-fromcodepoint.html","shorter")}}</div>
<h2 id="Syntax">Syntax</h2>
<pre class="syntaxbox notranslate">String<code>.fromCodePoint(<var>num1</var>[, ...[, <var>numN</var>]])</code></pre>
<h3 id="Parameters">Parameters</h3>
<dl>
<dt><code><var>num1</var>, ..., <var>numN</var></code></dt>
<dd>A sequence of code points.</dd>
</dl>
<h3 id="Return_value">Return value</h3>
<p>A string created by using the specified sequence of code points.</p>
<h3 id="Exceptions">Exceptions</h3>
<ul>
<li>A {{jsxref("Errors/Not_a_codepoint", "RangeError")}} is thrown if an invalid Unicode code point is given (e.g. <code>"RangeError: NaN is not a valid code point"</code>).</li>
</ul>
<h2 id="Description">Description</h2>
<p>This method returns a string (and <em>not</em> a {{jsxref("String")}} object).</p>
<p>Because <code>fromCodePoint()</code> is a static method of {{jsxref("String")}}, you must call it as <code>String.fromCodePoint()</code>, rather than as a method of a {{jsxref("String")}} object you created.</p>
<h2 id="Polyfill">Polyfill</h2>
<p>The <code>String.fromCodePoint()</code> method has been added to ECMAScript 2015 and may not be supported in all web browsers or environments yet.</p>
<p>Use the code below for a polyfill:</p>
<pre class="brush: js notranslate">if (!String.fromCodePoint) (function(stringFromCharCode) {
var fromCodePoint = function(_) {
var codeUnits = [], codeLen = 0, result = "";
for (var index=0, len = arguments.length; index !== len; ++index) {
var codePoint = +arguments[index];
// correctly handles all cases including `NaN`, `-Infinity`, `+Infinity`
// The surrounding `!(...)` is required to correctly handle `NaN` cases
// The (codePoint>>>0) === codePoint clause handles decimals and negatives
if (!(codePoint < 0x10FFFF && (codePoint>>>0) === codePoint))
throw RangeError("Invalid code point: " + codePoint);
if (codePoint <= 0xFFFF) { // BMP code point
codeLen = codeUnits.push(codePoint);
} else { // Astral code point; split in surrogate halves
// https://mathiasbynens.be/notes/javascript-encoding#surrogate-formulae
codePoint -= 0x10000;
codeLen = codeUnits.push(
(codePoint >> 10) + 0xD800, // highSurrogate
(codePoint % 0x400) + 0xDC00 // lowSurrogate
);
}
if (codeLen >= 0x3fff) {
result += stringFromCharCode.apply(null, codeUnits);
codeUnits.length = 0;
}
}
return result + stringFromCharCode.apply(null, codeUnits);
};
try { // IE 8 only supports `Object.defineProperty` on DOM elements
Object.defineProperty(String, "fromCodePoint", {
"value": fromCodePoint, "configurable": true, "writable": true
});
} catch(e) {
String.fromCodePoint = fromCodePoint;
}
}(String.fromCharCode));
</pre>
<h2 id="Examples">Examples</h2>
<h3 id="Using_fromCodePoint">Using <code>fromCodePoint()</code></h3>
<p>Valid input:</p>
<pre class="brush: js notranslate">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"
</pre>
<p>Invalid input:</p>
<pre class="brush: js notranslate">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
</pre>
<h3 id="Compared_to_fromCharCode">Compared to <code>fromCharCode()</code></h3>
<p>{{jsxref("String.fromCharCode()")}} cannot return supplementary characters (i.e. code points <code>0x010000</code> – <code>0x10FFFF</code>) by specifying their code point. Instead, it requires the UTF-16 surrogate pair in order to return a supplementary character:</p>
<pre class="brush: js notranslate">String.fromCharCode(0xD83C, 0xDF03); // Code Point U+1F303 "Night with
String.fromCharCode(55356, 57091); // Stars" == "\uD83C\uDF03"
</pre>
<p><code>String.fromCodePoint()</code>, 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):</p>
<pre class="brush: js notranslate">String.fromCodePoint(0x1F303); // or 127747 in decimal
</pre>
<h2 id="Specifications">Specifications</h2>
<table class="standard-table">
<thead>
<tr>
<th scope="col">Specification</th>
</tr>
</thead>
<tbody>
<tr>
<td>{{SpecName('ESDraft', '#sec-string.fromcodepoint', 'String.fromCodePoint')}}</td>
</tr>
</tbody>
</table>
<h2 id="Browser_compatibility">Browser compatibility</h2>
<p>{{Compat("javascript.builtins.String.fromCodePoint")}}</p>
<h2 id="See_also">See also</h2>
<ul>
<li>{{jsxref("String.fromCharCode()")}}</li>
<li>{{jsxref("String.prototype.charAt()")}}</li>
<li>{{jsxref("String.prototype.codePointAt()")}}</li>
<li>{{jsxref("String.prototype.charCodeAt()")}}</li>
</ul>
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