Issue working with numbers in Javascript

Question

I'm new in developing javascript apps, i have a doubt about a behaviour that i'm going to try to explain.

If i execute:

Number(5555555555555555);

Result: 5555555555555555

But if i execute:

Number(55555555555555555);

Result: 55555555555555550

Anybody can explain to me what is the reason of this? Thanks!!

Yes, the number is too big. If you need to deal with large numbers your best bet is to use some libray,. like mathjs http://mathjs.org/ — Keith, Sep 08 '17 at 11:16
?? Yes it is, you can open the console in a browser and execute it... — , Sep 08 '17 at 11:16
@vijoc - It is in fact valid javascript, well the `Number(12345)` part is. — Stuart, Sep 08 '17 at 11:17
Here is [another explanation of the context](http://2ality.com/2012/04/number-encoding.html) by Axel — sabithpocker, Sep 08 '17 at 11:20

score 1 · Accepted Answer · answered Sep 08 '17 at 11:18

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If you need to work with such big numbers I would suggest you use some of the big integer libraries such as this. The reason this happens as far as I know is the way processors and memory work. It's no related to some "bug" in JS.

answered Sep 08 '17 at 11:18

Biser A.

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score 1 · Answer 2 · answered Sep 08 '17 at 11:20

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Integers (numbers without a period or exponent notation) are accurate up to 15 digits. Javacript simply adds zeros to keep the number accurate in terms of its digit length.

Documentation

answered Sep 08 '17 at 11:20

Eternal

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Issue working with numbers in Javascript

2 Answers2