MAC addresses in JavaScript

I know that we can get the MAC address of a user via IE (ActiveX objects).

Is there a way to obtain a user's MAC address using JavaScript?


I concur with all the previous answers that it would be a privacy/security vulnerability if you would be able to do this directly from Javascript. There are two things I can think of:

  • Using Java (with a signed applet)
  • Using signed Javascript, which in FF (and Mozilla in general) gets higher privileges than normal JS (but it is fairly complicated to set up)

The quick and simple answer is No.

Javascript is quite a high level language and does not have access to this sort of information.


No you cannot get the MAC address in JavaScript, mainly because the MAC address uniquely identifies the running computer so it would be a security vulnerability.

Now if all you need is a unique identifier, I suggest you create one yourself using some cryptographic algorithm and store it in a cookie.

If you really need to know the MAC address of the computer AND you are developing for internal applications, then I suggest you use an external component to do that: ActiveX for IE, XPCOM for Firefox (installed as an extension).