Why are these two variables equal in JavaScript? [duplicate]

Question

I declared two variables like this and tried to compare them like this

var x  = 9999999999999999;
var y  = 10000000000000000;
x == y //returns true

What is the reason for this behavior?

The question is rather "why is 9999999999999999 being rounded to 10000000000000000" (check your JS console). — h2ooooooo
– h2ooooooo, Commented Nov 4, 2013 at 12:28
Yes, just reframed that as this. I observed the behaviour that you mentioned. — Narendra Yadala
– Narendra Yadala, Commented Nov 4, 2013 at 12:29
Worth reading: docs.oracle.com/cd/E19957-01/806-3568/ncg_goldberg.html — Roko C. Buljan
– Roko C. Buljan, Commented Nov 4, 2013 at 12:37

Community · Accepted Answer · 2017-05-23 12:03:24Z

1

Check this out:

"Javascript doesn't have integers, only 64-bit floats - and you've ran out of floating-point precision."

Thanks to the member Kos.

CommunityBot

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answered Nov 4, 2013 at 12:33

Matheus Gelinski

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