Grok’s paid plans start at $30/month, with a $75/month option for higher usage....

https://felixssuperperspective.brightsora.com/posts/can-two-supergrok-users-get-different-models-on-the-same-day

Grok’s paid plans start at $30/month, with a $75/month option for higher usage. Each plan limits you to about 10 prompts every 2 hours. There’s no free trial, so you’ll need to choose a plan upfront based on your typical prompt volume and budget.