I've also found few use cases for workers in the browser, but as the parent pointed out that's partly because of the limited and sluggish communication between threads in javascript. Just to offer an opposite perspective, serverside, almost any modestly heavy processing I do with nodejs happens in worker threads. These are pooled so they don't need to spin up. Blocking node's event loop is never an option. Fine to access a big dataset with an async call, but if you need to crunch that data before passing it to the client you pretty much have to use workers. [edit] obviously assuming you're not calling some command line process, and you're trying to chew though some large rendering of data using JS.