How to obtain lang attribute in HTML using JavaScript?

Question

How to obtain lang attribute in HTML using JavaScript?

Answer 1

Just.

document.getElementsByTagName('html')[0].getAttribute('lang');

And with the namespace

document.getElementsByTagName('html')[0].getAttribute('xml:lang');

Answer 2

If both attributes agree on their values (as they should), it's enough to read either of them. I'd suggest using

document.documentElement.lang