What is the maximum integer allowed in a javascript variable? [duplicate]

Question

Possible Duplicate:
What is JavaScript's Max Int? What's the highest Integer value a Number can go to without losing precision?

What is the maximum integer in javascript? I have a variable that starts in 0 and adds 100 each 0.1 seconds. What is the maximum number it can reach?

BTW, I thought this question had been answered before but I couldn't find it. If it is answered, please send me a link to it =) thanks!

Answer 1

JavaScript numbers are IEE 794 floating point double-precision values. There's a 53-bit mantissa (from memory), so that's pretty much the limit.

Now there are times when JavaScript semantics call for numbers to be cast to a 32-bit integer value, like array indexing and bitwise operators.

Answer 2

A javascript variable can have any value you like. If native support isn't sufficient, there are various libraries that provide support for unlimited precision arithmetic (e.g. BigInt.js).

The largest value for the ECMAScript Number Type is +ve infinity (but infinity isn't a number, it's a concept). The largest numeric value is given by Number.MAX_VALUE, which is just the maximum value representable by an IEEE 754 64-bit double-precision number.

Some quirks:

var x = Number.MAX_VALUE;
var y = x - 1;
var z = x - 2;

x == y; // true
x == z; // false

The range of contiguous integers representable in ECMAScript is from -2^53 to +2^53. The largest exponent is 2^1023.

Answer 3

It is 1.7976931348623157e+308

to try it yourself code it

CODE

alert(Number.MAX_VALUE);

http://jsfiddle.net/XHcZx/