OpenAI released its latest LLM, GPT-4, on 14th March 2023. There are the following methods to access GPT-4:
Access via ChatGPT Plus subscription.
Apply for the API waitlist: GPT-4 API waitlist (openai.com)
The new Bing runs on ChatGPT-4: Confirmed: the new Bing runs on OpenAI’s GPT-4 | Bing Search Blog
Poe.com from Quora: If without a subscription, limited access, only 1 query per day.
openai/evals: For a limited time, OpenAI will grant GPT-4 access to those who contribute high-quality evals.