I’ve noticed there’s been a lot of confusion around the term “GPT-o4 mini”, especially with how similar it sounds to “GPT-4o mini”. I wanted to clear things up and offer a few tips to help avoid misunderstandings when talking about the reasoning-focused model from OpenAI.
What is GPT-o4 mini?
GPT-o4 mini refers to OpenAI’s reasoning model released in April 2025, part of the o-series lineup (like o3 and o4).
It’s not the same as GPT-4o mini, which is a multimodal model that handles voice, image, and video.
How to Avoid Confusion:
Define it upfront
“GPT-o4 mini = OpenAI’s reasoning model (not the multimodal GPT-4o mini).”
Use consistent formatting
Stick with GPT-o4 mini every time. Avoid alternate spellings like “GPT-4o mini” or “o-4 mini” unless that’s what you actually mean.
Add a clarifying note in code or documentation
Using GPT-o4 mini (reasoning model, released April 2025)
Educate your team or readers
Mention the distinction during collaboration or discussion so people know you’re referring to the o-series model.
Final Tip:
Until OpenAI fixes the naming mess (Sam Altman himself said it’s confusing!), let’s help each other by being clear and consistent with model names.
That refers to … nothing. You make up your rules to call something by the wrong name
O
The name of the model is “o4” and then “o4-mini” is what is trained and offered.
You can think of the “O” like the first letter in OpenAI, with other brainwaves along that line not quite coming to fruition. No new logo, for example.
O - internal reasoning and thinking models You can thing of the O being oversight, you getting shut down by internal policies the AI is thinking about before it wants to trust you, or the oversight in making sure a verification system first works to ensure only highly-trusted individuals can be given timely access to dangerous faster text streams.
GPT
Here we’ve got generative pretrained transformer right up front. The actually technology name. A technology that cannot be trademarked (to some lawyer’s chagrin) - its name can only be used in remarkably confusing ways spitefully. It doesn’t have more than generating tokens that you receive, except for generating tool call recipients that you don’t receive, or generating on direct inputs you didn’t place.
So we throw logic to the wind after GPT-4. Because it is then internal model war and mega-fork. GPT-4-Turbo, a new training on a cheaper architecture to run. A 4o - omni, perhaps, then it just becomes about branding a recognizable name on different pulls from training runs and tuning them and shrinking them. Convolution of “project o200k” with what came before.
GPT-4o - overspecialized. When it is used as a substitute for Whisper, for DALL-E, for a TTS engine, for a voice-to-voice buddy, each on their own endpoint…