In what has already been a busy past few days for new model releases, OpenAI is capping off the week with a research preview of GPT-4.5.The company is touting the new system as its largest and best model for chat yet.In early testing, OpenAI says people found GPT-4.5 to be a more natural conversationalist, with the ability to convey warmth and display a kind of emotional intelligence.In one example shared by OpenAI, a person tells ChatGPT they're going through a hard time after failing a test.
Where the company's previous models, including GPT-4o and o3-mini, might commiserate with the individual before offering a long list of unsolicited advice, GPT-4.5 takes a different tact."Want to talk about what happened, or do you just need a distraction? I'm here either way," the chatbot says when powered by GPT-4.5.The gains shown by GPT-4.5 are the result of advancements OpenAI made in unsupervised learning.With unsupervised learning, a machine learning algorithm is given an unlabeled data set and left to its own devices to find patterns and insights.
GPT-4.5 doesn't "think" like the company's state-of-the-art reasoning models, but in training the new model OpenAI made architectural enhancements and gave it access to more data and compute power."The result is a model that has broader knowledge and a deeper understanding of the world, leading to reduced hallucinations," the company says.ADVERTISEMENTAdvertisementSpeaking of reduced hallucinations, OpenAI measured how much better GPT-4.5 in that regard.When put through SimpleQA, an OpenAI-designed benchmark that tests large language models on their ability to answer "straightforward but challenging knowledge questions," GPT-4.5 beat out o3-mini, GPT-4o and even o1 with a hallucination rate of 37.1 percent.
Obviously, the new model doesn't solve the problem of AI hallucinations altogether, but it is a step in the right direction.Despite its relative strengths over GPT-4o and o3-mini, GPT-4.5 isn't a direct replacement for those models.Compared to OpenAI's reasoning systems, GPT-4.5 is "a more general-purpose, innately smarter model." Additionally, it's not natively multimodal like GPT-4o, meaning it doesn't work with features like Voice Mode, video or screensharing.It’s also "a very large and compute-intensive model."It's best to think of GPT-4.5 as a stepping stone to systems OpenAI plans to offer in the future.
In fact, Sam Altman said as much earlier this month when he shared the company's roadmap, noting GPT-4.5 would be "our last non-chain-of-thought model" — referring to the fact that the new system doesn't solve problems by tackling them step by step like OpenAI's reasoning models do.Its successor, GPT-5, will likely integrate many of OpenAI's latest technologies, including its frontier o3 model.OpenAI reiterated that today, saying it plans to bring GPT-4.5's "unique strengths, including broader knowledge, stronger intuition, and greater 'EQ,' to all users in future models."In the meantime, ChatGPT Pro subscribers can begin using GPT-4.5 starting today, with Pro and Team users slated to gain access starting next week.
