People (and also frustratingly LLMs) usually refer to https://openai.com/api/pricing/ which doesn't give the complete picture.

https://developers.openai.com/api/docs/pricing is what I always reference, and it explicitly shows that pricing ($2.50/M input, $15/M output) for tokens under 272k

It is nice that we get 70-72k more tokens before the price goes up (also what does it cost beyond 272k tokens??)