What is the notation of equal or almost equal?

Question

I have a measure X and the value of $X$ is equal to or almost $1000$. This can be $X=1000$, $X=999$, or $X=998$.

Is it correct if I use the symbol $≃$ such that $X ≃ 1000$?

Answer 1

I have seen that, but we have $\approx$ available in MathJax from \approx. I think it is a better choice.

Answer 2

Most commonly used is definitely the double tilde symbol:

$\approx$ $\approx$

≈ (U+2248)

But there are quite a few alternative symbols: https://en.wikipedia.org/wiki/Equals_sign#Approximately_equal