[tedsanders]

o3 pro is based on o3 and its style and outputs will be quite similar to o3.

As an analogy, think of it like this:

o3-low ~ Ford Mustang with the accelerator gently pressed

o3-medium ~ Ford Mustang with the accelerator pressed

o3-high ~ Ford Mustang with the accelerator heavily pressed

o3 pro ~ Ford Mustang GT

Even though a Mustang GT is a different car than a Mustang, you don’t give it a totally different name (eg Palomino). The similarity in name signals it has a lot of the same characteristics but a souped up engine. Same for o3 pro.

Fun fact: before GPT-4, we had a unified naming scheme for models that went {modality}-{size}-{version}, which resulted in names like text-davinci-002. We considered launching GPT-4 as something like text-earhart-001, but since everyone was calling it GPT-4 anyway, we abandoned that system to use the name GPT-4 that everyone had already latched onto. Kind of funny how our original unified naming scheme made room for 999 versions, but we didn't make it past 3.

Edit: When I say the Mustang GT is a different car than a Mustang - I mean it literally. If you bought a Mustang GT and someone delivered a Mustang with a different trim, you wouldn't say "great, this is just what I ordered, with the same features/behavior/value." That we call it a different trim is a linguistic choice to signal to consumers that it's very similar, and built on the same production line, but comes with a different engine or different features. Similar to o3 pro.

[dwohnitmok]

Can you elaborate on what you mean that o3 pro is a GT? In particular I don't understand how to reconcile what you're saying that o3 pro is in some way fundamentally different from o3 (albeit based on o3) with this tweet:

> As o3-pro uses the same underlying model as o3, full safety details can be found in the o3 system card.

https://x.com/OpenAI/status/1932530423911096508

[tedsanders]

Yeah, I totally get the confusion here. Unfortunately I can't give the recipe behind our models, so there's going to be some irreducible blurriness here, but the following statements are all true:

- o3 pro is based on o3

- o3 pro uses the same underlying model as o3

- o3 pro is similar to o3, but is a distinct thing that's smarter and slower

- o3 pro is not o3 with longer reasoning

In my analogy, o3 pro vs o3 is more than just an input parameter (e.g., not just the accelerator input) but less than a full difference in model (e.g., Ford Mustang vs F150). It's in between, kind of like car trim with the same body but a stronger engine. Imperfect analogy, and I apologize if this doesn't feel like it adds any clarity. At the end of the day, it doesn't really matter how it works - what matters is if people find it worth using.

[stonogo]

This analogy might work better if the Mustang GT weren't, in fact, the same car as the Mustang. It's just a trim level, not a different car.