Is there a big difference between GPT-4o mini and 4o?

Yeah, the speed is almost similar, but the coding accuracy is definitely better with 4o.

Personally, I use GPT-4o mini quite often because it offers great value for the quality of responses. That said, GPT-4o is better for more detailed and longer contexts, but for everyday questions, mini is sufficient.

Well, I didn't really notice much difference lol. There are a lot of exaggerated reviews, so I recommend trying it yourself.