OpenAI has released a ton of improvements for its chatbot, ChatGPT, in recent months, but it’s been a while since we’ve had a core model update. While we await for GPT-5, which OpenAI seems pretty ambitious with, the company has launched a mid-step upgrade in the meantime—GPT-4.5.
OpenAI has officially launched GPT-4.5, its newest and largest language model to date. While not considered a “frontier” model, as per the company itself, GPT-4.5 nonetheless offers significant improvements in computational efficiency, writing quality, world knowledge, and reduced hallucination rates compared to its predecessor, GPT-4. The model is being made available as a “research preview,” which means it will first undergo a controlled rollout initially focused on gathering user feedback and on giving it final touches before it becomes generally available.
GPT-4.5 is reported to have a greater than tenfold improvement in computational efficiency compared to GPT-4. This means the model can achieve similar or better results with significantly less processing power. OpenAI also says GPT-4.5 has enhanced writing capabilities and expanded world knowledge. This means that we should also have improvements in areas like text generation, summarization, translation, and question answering. And we should also have a “refined personality” over previous models. We’re not sure about the exact meaning of that, but it could mean we might have a more consistent and engaging conversational style with this model that doesn’t read as robotically.
A key focus of GPT-4.5’s development has been minimizing hallucinations—instances where the model confidently generates false or nonsensical information. According to OpenAI, GPT-4.5 hallucinates less than GPT-4o, and only slightly less than o1. GPT-4.5 has been trained using a combination of “new supervision techniques” alongside established methods like supervised fine-tuning (SFT) and reinforcement learning from human feedback (RLHF).
Despite these advancements, OpenAI is clear that GPT-4.5 is not a frontier model—and for some stuff, it might not even be a massive step forward in any way. It doesn’t feature any brand-new or significantly improved capabilities, and as a matter of fact, GPT-4.5 can actually perform “below that of o1, o3-mini, and deep research on most preparedness evaluations.” This is an upgrade over GPT-4, sure, but the model the company is preparing as its next game-breaking model is GPT-5. This is just to hold us over until that arrives. Still, it’s better than nothing at all.
As a reminder, CEO Sam Altman recently acknowledged on Twitter/X the growing complexity of OpenAI’s offerings, and said that the company’s goal is to make AI “just work” for users. The company’s immediate plan involved the release of this model, codenamed Orion, which will be the company’s final release before transitioning exclusively to a “chain-of-thought” approach for future models. This method, already used by GPT o1/o3 and DeepSeek models, breaks down prompts into several steps, resulting in more reliable answers and fewer AI hallucinations.
Looking further ahead, OpenAI plans to introduce GPT-5, which the company thinks about as an integrated system consolidating various technologies. This includes the full o3 model’s functionalities (right now we only have o3-mini, and the full o3 model is reserved for the release of GPT-5). GPT-5 aims to support features like voice interaction, canvas capabilities, enhanced search, and deep research tools. Details remain scarce so far, but the company has indicated that the availability of specific tools may vary across subscription tiers.
GPT-4.5 is now rolling out as a “research preview.” ChatGPT Pro users will gain access to the model today, and it should also arrive for Plus and Team users by next week. It’s not clear if, or when, the model might roll out for free users, but if this goes anything similar to the initial GPT-4 rollout, we might see it pop up first on other chatbots such as Microsoft Copilot before it lands for free ChatGPT.
