How can i test my game in 800*600 px ?

Hello all

How can i test my game like Kongregate and miniclip frames, I mean 800 by 600 pix frames that will hide any part above these sizes.

I have the Chrome addon and also firefox, But i want to test it like the games sites to be sure every thing is fine.

Is there a script can i upload to my dropbox Or is there a site i can upload the game then delete it by myself.

Thanks for any help guys.

I would either think to just resize the browser window, or you just embed it inside an iframe with a 800x600 px size.

I'm already have the resize browser addon.

But after playing some games on kongregate it's seems that the height less than 600 px in there frame.