Grok’s paid plans start at $20/month for up to 20 prompts every 2 hours and...

https://telegra.ph/How-Many-Prompts-Do-You-Get-on-Grok-Free-Tier-Every-2-Hours-10-14

Grok’s paid plans start at $20/month for up to 20 prompts every 2 hours and $50/month for 60 prompts in the same timeframe. Each account is capped at roughly 10 prompts per 2 hours