# Testing numerical accuracy of browsers

According to the standard, only the arithmetic operations in Javascript need to be correctly rounded, the functions in `Math`

does not have any accuracy requirements.

But out in the real world, browsers are a bit better than that, we have a feeling that the functions in `Math`

are reasonably accurate, but if you need to be convinced (like me) then you should look at https://github.com/JensNockert/accuracy.js which fuzz tests most of the operations in `Math`

that have a tendency to be inaccurate.

If you want to be even more convinced, generate more test cases using generate.rb.

Ps. `sin`

, `cos`

and `tan`

are missing, their periodicity makes them hard to fuzz using this technique.

## Update

- I fuzzed on Windows as well, and Chrome on Windows does not provide
`sqrt`

with correct rounding, a bug has been filed. Firefox and Opera provide as much precision on Windows as on OS X.