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---
title: Math
slug: Web/JavaScript/Reference/Global_Objects/Math
tags:
- JavaScript
- Math
- Namespace
- NeedsTranslation
- Reference
- TopicStub
translation_of: Web/JavaScript/Reference/Global_Objects/Math
---
<div></div>
<div>{{JSRef}}</div>
<p><strong><code>Math</code></strong> is a built-in object that has properties and methods for mathematical constants and functions. It’s not a function object.</p>
<p><code>Math</code> works with the {{jsxref("Number")}} type. It doesn't work with {{jsxref("BigInt")}}.</p>
<h2 id="Description">Description</h2>
<p>Unlike many other global objects, <code>Math</code> is not a constructor. All properties and methods of <code>Math</code> are static. You refer to the constant pi as <code>Math.PI</code> and you call the sine function as <code>Math.sin(<var>x</var>)</code>, where <code><var>x</var></code> is the method’s argument. Constants are defined with the full precision of real numbers in JavaScript.</p>
<div class="note">
<p><strong>Note:</strong> Many <code>Math</code> functions have a precision that’s <em>implementation-dependent.</em></p>
<p>This means that different browsers can give a different result. Even the same JavaScript engine on a different OS or architecture can give different results!</p>
</div>
<h2 id="Static_properties">Static properties</h2>
<dl>
<dt>{{jsxref("Math.E")}}</dt>
<dd>Euler's constant and the base of natural logarithms; approximately <code>2.718</code>.</dd>
<dt>{{jsxref("Math.LN2")}}<code>lllllđđlđ</code></dt>
<dd>lllllđđ v<img alt="" src="https://mdn.mozillademos.org/files/14829/trigonometry.png" style="height: 166px; width: 200px;">ili ga ti tu of <code>2</code>; approximately <code>0.693</code>.</dd>
<dt>{{jsxref("Math.LN10")}}</dt>
<dd>Natural logarithm of <code>10</code>; approximately <code>2.303</code>.</dd>
<dt>{{jsxref("Math.LOG2E")}}</dt>
<dd>Base-2 logarithm of <code>E</code>; approximately <code>1.443</code>.</dd>
<dt>{{jsxref("Math.LOG10E")}}</dt>
<dd>Base-10 logarithm of <code>E</code>; approximately <code>0.434</code>.</dd>
<dt>{{jsxref("Math.PI")}}</dt>
<dd>Ratio of the a circle's circumference to its diameter; approximately <code>3.14159</code>.</dd>
<dt>{{jsxref("Math.SQRT1_2")}}</dt>
<dd>Square root of ½ (or equivalently, <sup>1</sup>/<sub>√2</sub>); approximately <code>0.707</code>.</dd>
<dt>{{jsxref("Math.SQRT2")}}</dt>
<dd>Square root of <code>2</code>; approximately <code>1.414</code>.</dd>
</dl>
<h2 id="Static_methods">Static methods</h2>
<dl>
<dt>{{jsxref("Global_Objects/Math/abs", "Math.abs(<var>x</var>)")}}</dt>
<dd>Returns the absolute value of <code><var>x</var></code>.</dd>
<dt>{{jsxref("Global_Objects/Math/acos", "Math.acos(<var>x</var>)")}}</dt>
<dd>Returns the arccosine of <code><var>x</var></code>.</dd>
<dt>{{jsxref("Global_Objects/Math/acosh", "Math.acosh(<var>x</var>)")}}</dt>
<dd>Returns the hyperbolic arccosine of <code><var>x</var></code>.</dd>
<dt>{{jsxref("Global_Objects/Math/asin", "Math.asin(<var>x</var>)")}}</dt>
<dd>Returns the arcsine of <code><var>x</var></code>.</dd>
<dt>{{jsxref("Global_Objects/Math/asinh", "Math.asinh(<var>x</var>)")}}</dt>
<dd>Returns the hyperbolic arcsine of a number.</dd>
<dt>{{jsxref("Global_Objects/Math/atan", "Math.atan(<var>x</var>)")}}</dt>
<dd>Returns the arctangent of <code><var>x</var></code>.</dd>
<dt>{{jsxref("Global_Objects/Math/atanh", "Math.atanh(<var>x</var>)")}}</dt>
<dd>Returns the hyperbolic arctangent of <code><var>x</var></code>.</dd>
<dt>{{jsxref("Global_Objects/Math/atan2", "Math.atan2(<var>y</var>, <var>x</var>)")}}</dt>
<dd>Returns the arctangent of the quotient of its arguments.</dd>
<dt>{{jsxref("Global_Objects/Math/cbrt", "Math.cbrt(<var>x</var>)")}}</dt>
<dd>Returns the cube root of <code><var>x</var></code>.</dd>
<dt>{{jsxref("Global_Objects/Math/ceil", "Math.ceil(<var>x</var>)")}}</dt>
<dd>Returns the smallest integer greater than or equal to <code><var>x</var></code>.</dd>
<dt>{{jsxref("Global_Objects/Math/clz32", "Math.clz32(<var>x</var>)")}}</dt>
<dd>Returns the number of leading zeroes of the 32-bit integer <code><var>x</var></code>.</dd>
<dt>{{jsxref("Global_Objects/Math/cos", "Math.cos(<var>x</var>)")}}</dt>
<dd>Returns the cosine of <code><var>x</var></code>.</dd>
<dt>{{jsxref("Global_Objects/Math/cosh", "Math.cosh(<var>x</var>)")}}</dt>
<dd>Returns the hyperbolic cosine of <code><var>x</var></code>.</dd>
<dt>{{jsxref("Global_Objects/Math/exp", "Math.exp(<var>x</var>)")}}</dt>
<dd>Returns <code>E<var><sup>x</sup></var></code>, where <code><var>x</var></code> is the argument, and <code>E</code> is Euler's constant (<code>2.718</code>…, the base of the natural logarithm).</dd>
<dt>{{jsxref("Global_Objects/Math/expm1", "Math.expm1(<var>x</var>)")}}</dt>
<dd>Returns subtracting <code>1</code> from <code>exp(<var>x</var>)</code>.</dd>
<dt>{{jsxref("Global_Objects/Math/floor", "Math.floor(<var>x</var>)")}}</dt>
<dd>Returns the largest integer less than or equal to <code><var>x</var></code>.</dd>
<dt>{{jsxref("Global_Objects/Math/fround", "Math.fround(<var>x</var>)")}}</dt>
<dd>Returns the nearest <a href="https://en.wikipedia.org/wiki/Single-precision_floating-point_format" title="link to the wikipedia page on single precision">single precision</a> float representation of <code><var>x</var></code>.</dd>
<dt>{{jsxref("Global_Objects/Math/hypot", "Math.hypot([<var>x</var>[, <var>y</var>[, …]]])")}}</dt>
<dd>Returns the square root of the sum of squares of its arguments.</dd>
<dt>{{jsxref("Global_Objects/Math/imul", "Math.imul(<var>x</var>, <var>y</var>)")}}</dt>
<dd>Returns the result of the 32-bit integer multiplication of <code><var>x</var></code> and <code><var>y</var></code>.</dd>
<dt>{{jsxref("Global_Objects/Math/log", "Math.log(<var>x</var>)")}}</dt>
<dd>Returns the natural logarithm (㏒<sub>e</sub>; also, ㏑) of <code><var>x</var></code>.</dd>
<dt>{{jsxref("Global_Objects/Math/log1p", "Math.log1p(<var>x</var>)")}}</dt>
<dd>Returns the natural logarithm (㏒<sub>e</sub>; also ㏑) of <code>1 + <var>x</var></code> for the number <code><var>x</var></code>.</dd>
<dt>{{jsxref("Global_Objects/Math/log10", "Math.log10(<var>x</var>)")}}</dt>
<dd>Returns the base-10 logarithm of <code><var>x</var></code>.</dd>
<dt>{{jsxref("Global_Objects/Math/log2", "Math.log2(<var>x</var>)")}}</dt>
<dd>Returns the base-2 logarithm of <code><var>x</var></code>.</dd>
<dt>{{jsxref("Global_Objects/Math/max", "Math.max([<var>x</var>[, <var>y</var>[, …]]])")}}</dt>
<dd>Returns the largest of zero or more numbers.</dd>
<dt>{{jsxref("Global_Objects/Math/min", "Math.min([<var>x</var>[, <var>y</var>[, …]]])")}}</dt>
<dd>Returns the smallest of zero or more numbers.</dd>
<dt>{{jsxref("Global_Objects/Math/pow", "Math.pow(<var>x</var>, <var>y</var>)")}}</dt>
<dd>Returns base <code><var>x</var></code> to the exponent power <code><var>y</var></code> (that is, <code><var>x</var><var><sup>y</sup></var></code>).</dd>
<dt>{{jsxref("Global_Objects/Math/random", "Math.random()")}}</dt>
<dd>Returns a pseudo-random number between <code>0</code> and <code>1</code>.</dd>
<dt>{{jsxref("Global_Objects/Math/round", "Math.round(<var>x</var>)")}}</dt>
<dd>Returns the value of the number <code><var>x</var></code> rounded to the nearest integer.</dd>
<dt>{{jsxref("Global_Objects/Math/sign", "Math.sign(<var>x</var>)")}}</dt>
<dd>Returns the sign of the <code><var>x</var></code>, indicating whether <code><var>x</var></code> is positive, negative, or zero.</dd>
<dt>{{jsxref("Global_Objects/Math/sin", "Math.sin(<var>x</var>)")}}</dt>
<dd>Returns the sine of <code><var>x</var></code>.</dd>
<dt>{{jsxref("Global_Objects/Math/sinh", "Math.sinh(<var>x</var>)")}}</dt>
<dd>Returns the hyperbolic sine of <code><var>x</var></code>.</dd>
<dt>{{jsxref("Global_Objects/Math/sqrt", "Math.sqrt(<var>x</var>)")}}</dt>
<dd>Returns the positive square root of <code><var>x</var></code>.</dd>
<dt>{{jsxref("Global_Objects/Math/tan", "Math.tan(<var>x</var>)")}}</dt>
<dd>Returns the tangent of <code><var>x</var></code>.</dd>
<dt>{{jsxref("Global_Objects/Math/tanh", "Math.tanh(<var>x</var>)")}}</dt>
<dd>Returns the hyperbolic tangent of <code><var>x</var></code>.</dd>
<dt>{{jsxref("Global_Objects/Math/trunc", "Math.trunc(<var>x</var>)")}}</dt>
<dd>Returns the integer portion of <code><var>x</var></code>, removing any fractional digits.</dd>
</dl>
<h2 id="Examples">Examples</h2>
<h3 id="Converting_between_degrees_and_radians">Converting between degrees and radians</h3>
<p>The trigonometric functions <code>sin()</code>, <code>cos()</code>, <code>tan()</code>, <code>asin()</code>, <code>acos()</code>, <code>atan()</code>, and <code>atan2()</code> expect (and return) angles in <em>radians</em>.</p>
<p>Since humans tend to think in degrees, and some functions (such as CSS transforms) can accept degrees, it is a good idea to keep functions handy that convert between the two:</p>
<pre class="brush: js"><code class="language-js"><span class="keyword token">function</span> <span class="function token">degToRad</span><span class="punctuation token">(</span><span class="parameter token">degrees</span><span class="punctuation token">)</span> <span class="punctuation token">{</span>
<span class="keyword token">return</span> degrees <span class="operator token">*</span> (Math<span class="punctuation token">.</span><span class="constant token">PI</span> <span class="operator token">/</span> <span class="number token">180</span><span class="punctuation token">);</span>
<span class="punctuation token">}</span><span class="punctuation token">;</span></code>
function radToDeg(rad) {
return rad / (Math.PI / 180);
};</pre>
<h3 id="Calculating_the_height_of_an_equalateral_triangle">Calculating the height of an equalateral triangle</h3>
<p>If we want to calculate the height of an equalateral triangle, and we know its side length is 100, we can use the formulae <em>length of the adjacent multiplied by the tangent of the angle is equal to the opposite.</em></p>
<p><img alt="" src="https://mdn.mozillademos.org/files/14829/trigonometry.png" style="display: block; margin: 0 auto;"></p>
<p>In JavaScript, we can do this with the following:</p>
<pre class="brush: js">50 * Math.tan(degToRad(60)).</pre>
<p>We use our <code>degToRad()</code> function to convert 60 degrees to radians, as <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Math/tan"><code>Math.tan()</code></a> expects an input value in radians.</p>
<h3 id="Returning_a_random_integer_between_two_bounds">Returning a random integer between two bounds</h3>
<p>This can be achieved with a combination of <code><a href="/en-US/docs/Web/JavaScript/Reference/Global_Objects/Math/random">Math.random()</a></code> and <code><a href="/en-US/docs/Web/JavaScript/Reference/Global_Objects/Math/floor">Math.floor()</a></code>:</p>
<pre class="brush: js">function random(min, max) {
const num = Math.floor(Math.random() * (max - min + 1)) + min;
return num;
}
random(1, 10);</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-math-object', 'Math')}}</td>
</tr>
</tbody>
</table>
<h2 id="Browser_compatibility">Browser compatibility</h2>
<p>{{Compat("javascript.builtins.Math")}}</p>
<h2 id="See_also">See also</h2>
<ul>
<li>{{jsxref("Number")}}</li>
</ul>
|
