Also don't forget to add the ~$10-$20k in legal fees for sponsoring an H1b on top of that.
When I moved to the US (to work for one of the companies on that list of tech firms), their attitude was "Do you need a visa?" (I didn't, as it happened) "Just let us know, we'll get you a H-1B". There wasn't any shadow of a doubt in their mind that it was much more than a formality.
$325 base + $1500 AICWA + $500 fraud protection fee + [potential $4000 Public Law 114-113 fee] + [optional $1125 premium processing fee] = $6325 + [optional $1125].
Legal fees vary from $500 to $3000 on top of that.
But regardless, also add the non-salary benefits, of course: non-discretionary bonuses, stock grants, etc.