MDN’s new design is in Beta! A sneak peek:

The Number.MIN_SAFE_INTEGER constant represents the minimum safe integer in JavaScript (-(253 - 1)).

Property attributes of Number.MIN_SAFE_INTEGER
Writable no
Enumerable no
Configurable no


The MIN_SAFE_INTEGER constant has a value of -9007199254740991. The reasoning behind that number is that JavaScript uses double-precision floating-point format numbers as specified in IEEE 754 and can only safely represent numbers between -(253 - 1) and 253 - 1.

Because MIN_SAFE_INTEGER is a static property of Number, you always use it as Number.MIN_SAFE_INTEGER, rather than as a property of a Number object you created.


Number.MIN_SAFE_INTEGER // -9007199254740991
-(Math.pow(2, 53) - 1)  // -9007199254740991


Specification Status Comment
ECMAScript 2015 (6th Edition, ECMA-262)
The definition of 'Number.MIN_SAFE_INTEGER' in that specification.
Standard Initial definition.
ECMAScript Latest Draft (ECMA-262)
The definition of 'Number.MIN_SAFE_INTEGER' in that specification.

Browser compatibility

FeatureChromeFirefoxEdgeInternet ExplorerOperaSafari
Basic Support3431(Yes)(No)(Yes)9
FeatureAndroidChrome for AndroidEdge mobileFirefox for AndroidIE mobileOpera AndroidiOS Safari
Basic Support(Yes)(Yes)(Yes)31(No)(Yes)9

See also

Document Tags and Contributors

 Contributors to this page: fscholz, jameshkramer, kdex, fleurdeswift, Mingun, realityking, Nevallem
 Last updated by: fscholz,