Grok’s paid plans start at $15/month and $75/month, with a cap of about 10...

https://fernandosbrilliantnews.iamarrows.com/how-do-grok-api-tool-charges-stack-on-top-of-token-costs

Grok’s paid plans start at $15/month and $75/month, with a cap of about 10 prompts every 2 hours to manage usage. There’s no free trial available, so you commit upfront