Math.sqrt()

The Math.sqrt() function returns the square root of a number, that is

∀x≥0,Math.sqrt(x)=x=the uniquey≥0such thaty2=x\forall x \geq 0, \mathtt{Math.sqrt(x)} = \sqrt{x} = \text{the unique} \; y \geq 0 \; \text{such that} \; y^2 = x

Syntax

Math.sqrt(x)

Parameters

x
A number.

Return value

The square root of the given number. If the number is negative, NaN is returned.

Description

If the value of x is negative, Math.sqrt() returns NaN.

Because sqrt() is a static method of Math, you always use it as Math.sqrt(), rather than as a method of a Math object you created (Math is not a constructor).

Examples

Using Math.sqrt()

Math.sqrt(9); // 3
Math.sqrt(2); // 1.414213562373095

Math.sqrt(1);  // 1
Math.sqrt(0);  // 0
Math.sqrt(-1); // NaN
Math.sqrt(-0); // -0

Specifications

Specification Status Comment
ECMAScript 1st Edition (ECMA-262) Standard Initial definition. Implemented in JavaScript 1.0.
ECMAScript 5.1 (ECMA-262)
The definition of 'Math.sqrt' in that specification.		 Standard  
ECMAScript 2015 (6th Edition, ECMA-262)
The definition of 'Math.sqrt' in that specification.		 Standard  
ECMAScript Latest Draft (ECMA-262)
The definition of 'Math.sqrt' in that specification.		 Draft  

Browser compatibility

Update compatibility data on GitHub
DesktopMobileServer
ChromeEdgeFirefoxInternet ExplorerOperaSafariAndroid webviewChrome for AndroidFirefox for AndroidOpera for AndroidSafari on iOSSamsung InternetNode.js
sqrtChrome Full support YesEdge Full support 12Firefox Full support 1IE Full support YesOpera Full support YesSafari Full support YesWebView Android Full support YesChrome Android Full support YesFirefox Android Full support 4Opera Android Full support YesSafari iOS Full support YesSamsung Internet Android Full support Yesnodejs Full support Yes

Legend

Full support  
Full support

See also

Related Topics
  1. Standard built-in objects
  2. Math
  3. Properties
    1. Math.E
    2. Math.LN10
    3. Math.LN2
    4. Math.LOG10E
    5. Math.LOG2E
    6. Math.PI
    7. Math.SQRT1_2
    8. Math.SQRT2
  4. Methods
    1. Math.abs()
    2. Math.acos()
    3. Math.acosh()
    4. Math.asin()
    5. Math.asinh()
    6. Math.atan()
    7. Math.atan2()
    8. Math.atanh()
    9. Math.cbrt()
    10. Math.ceil()
    11. Math.clz32()
    12. Math.cos()
    13. Math.cosh()
    14. Math.exp()
    15. Math.expm1()
    16. Math.floor()
    17. Math.fround()
    18. Math.hypot()
    19. Math.imul()
    20. Math.log()
    21. Math.log10()
    22. Math.log1p()
    23. Math.log2()
    24. Math.max()
    25. Math.min()
    26. Math.pow()
    27. Math.random()
    28. Math.round()
    29. Math.sign()
    30. Math.sin()
    31. Math.sinh()
    32. Math.sqrt()
    33. Math.tan()
    34. Math.tanh()
    35. Math.trunc()
  5. Inheritance:
  6. Object
  7. Properties
    1. Object.prototype.__count__
    2. Object.prototype.__noSuchMethod__
    3. Object.prototype.__parent__
    4. Object.prototype.__proto__
    5. Object.prototype.constructor
  8. Methods
    1. Object.prototype.__defineGetter__()
    2. Object.prototype.__defineSetter__()
    3. Object.prototype.__lookupGetter__()
    4. Object.prototype.__lookupSetter__()
    5. Object.prototype.hasOwnProperty()
    6. Object.prototype.isPrototypeOf()
    7. Object.prototype.propertyIsEnumerable()
    8. Object.prototype.toLocaleString()
    9. Object.prototype.toSource()
    10. Object.prototype.toString()
    11. Object.prototype.unwatch()
    12. Object.prototype.valueOf()
    13. Object.prototype.watch()
    14. Object.setPrototypeOf()