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
ECMAScript Latest Draft (ECMA-262)
The definition of 'Math.sqrt' in that specification.

Browser compatibility

Update compatibility data on GitHub
DesktopMobileServer
ChromeEdgeFirefoxInternet ExplorerOperaSafariAndroid webviewChrome for AndroidFirefox for AndroidOpera for AndroidSafari on iOSSamsung InternetNode.js
sqrtChrome Full support 1Edge Full support 12Firefox Full support 1IE Full support 3Opera Full support 3Safari Full support 1WebView Android Full support 1Chrome Android Full support 18Firefox Android Full support 4Opera Android Full support 10.1Safari iOS Full support 1Samsung Internet Android Full support 1.0nodejs 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()