Grok’s paid plans start at $12/month and go up to $50/month, with a cap of...

https://sierra-wiki.win/index.php/Why_Does_My_Grok_Plan_Not_Show_Which_Model_Answered_My_Prompt%3F

Grok’s paid plans start at $12/month and go up to $50/month, with a cap of roughly 10 prompts every 2 hours to manage usage. There’s no free trial available, so you’ll want to be sure the plan fits your needs before subscribing