Gemini 2.5 Pro Experimental (a frontier model) has 5 RPM and 25 RPD.

Gemini 2.5 Flash Preview 04-17 another powerful model has 10 and 500.

OpenAI also allows you to use their API for free if you agree to share the tokens.

What are "RPM" and "RPD"? I assume not Revolutions Per Minute?