How to purchase chat gpt 4 subscription for API?

API
1

We are using chat gpt 3 and we want to upgrade it to chat gpt4. How do we make purchase of it.
Please provide me guidance in this.
Thanks

2

If you are already using GPT-3.5-Turbo via platform.openai.com, then you just need to swap the model name out for GPT-4-Turbo or GPT-4o.

3

…and pay potentialy 60x more per API call.

https://openai.com/api/pricing/