Is OpenAI GPT free?

Hello there, I was wondering if you could clarify something for me. I've been hearing a lot about OpenAI GPT and its capabilities, but I'm a bit confused about the cost aspect. Specifically, I'm wondering if OpenAI GPT is available for free to use, or do users need to pay for access to its features? I'd appreciate any insights you could provide on this matter. Thank you in advance for your help!