👾 GPT-4.5: A New King on the Throne?

February 27 marked the end of a long wait. After months of speculation, numerous rumors and intense hype, which was also fueled by prominent OpenAI employees themselves, OpenAI officially presented its latest model: GPT-4.5. CEO Sam Altman had already announced in advance that GPT-4.5 would be the last model in the series of so-called “non-reasoners” before GPT-5 is to be released in a few months - a model in which OpenAI intends to combine reasoning and non-reasoning capabilities in a common architecture for the first time. In view of this preliminary information, it was hardly surprising that GPT-4.5 was inferior to OpenAI's already published reasoner models in many benchmarks.

Nevertheless, the release sparked an extremely lively and controversial debate, particularly on the social media platform X. Users passionately discussed whether GPT-4.5 could actually live up to the high expectations or whether it was a bitter disappointment. Above all, the fact that many users felt that the model's innovations were too minor, almost “underwhelming”, caused widespread dissatisfaction. OpenAI itself has so far only commented sparingly on this debate, giving rise to the feeling in many places that the majority of users have been disappointed.

In this article, I would therefore like to take a closer look and take stock of OpenAI's latest model. What exactly are the new features, where has GPT-4.5 been improved and what strategy is OpenAI pursuing by presenting an intermediate iteration shortly before the release of an eagerly awaited successor? We first take an in-depth look at the available data and then analyze both sides of this heated debate in detail. Finally, we try to find an answer to the question of whether the release of GPT-4.5 was ultimately justified or perhaps just an unnecessary interim step.

What Are the New Features of GPT-4.5?

OpenAI recently presented its latest language model, GPT-4.5, which brings significant advances over its predecessor GPT-4o. One of the most outstanding new features is the greatly improved emotional intelligence, which gives users the feeling of interacting with an attentive and empathetic conversation partner. According to OpenAI CEO Sam Altman, the model is now able to recognize human emotions more precisely and react empathetically accordingly. This not only leads to more natural conversations, but also expands the possible applications of AI, for example in areas such as therapy, customer service or education, where empathic communication is crucial.

In addition, GPT-4.5 has a significantly expanded knowledge base and a deeper understanding of the world, resulting in greater precision and reliability of its responses. The model responds more reliably to complex and wide-ranging topics and at the same time significantly reduces the rate of so-called “hallucinations”, i.e. incorrect but seemingly plausible answers. Initial tests show that the hallucination rate has fallen from around 60 percent with GPT-4o to 37 percent. This improvement is not only remarkable in quantitative terms, but also represents a decisive breakthrough in qualitative terms, as AI systems can now be increasingly used in areas where it is not immediately or easily possible to verify answers - for example in sensitive areas such as medical diagnosis, legal advice or complex technical support.

Another significant but often underestimated advance is the model's ability to extract and accurately access even the most minimal contextual information from conversations. Even earlier models such as GPT-4 impressed with their ability to correctly interpret implicit cues. However, GPT-4.5 takes this feature to a new level: even when only extremely subtle hints are present, the model is able to reliably understand the context of the conversation and respond accordingly. This feature is crucial for authentic and natural interactions that feel intuitive and comprehensible to users. Like a high-resolution audio recording that clearly reproduces even the finest nuances, GPT-4.5 enables deeper and higher quality communication that makes users feel truly understood.

Despite all these remarkable improvements, GPT-4.5 also comes with significant challenges, particularly in terms of high operating costs. Due to its size and complexity, the model is extremely computationally intensive, which translates into significantly higher costs compared to GPT-4o. OpenAI has therefore already considered restricting access to the model for developers. In concrete terms, this means that developers will have to expect significantly higher API prices: While GPT-4o still cost 2.50 US dollars per million input tokens and 10 US dollars per million output tokens, these prices will rise to 75 US dollars and 150 US dollars respectively for GPT-4.5. These costs could deter smaller companies and independent developers in particular, making it more difficult for the model to be widely accessible.

Nevertheless, the advantages clearly outweigh the disadvantages. The combination of improved emotional intelligence, reduced risk of hallucination and outstanding context sensitivity makes GPT-4.5 a major step towards reliable and trustworthy AI systems. In particular, the greatly reduced error rate combined with high precision and intuitive understanding of subtle conversational cues opens up completely new application possibilities. In the long term, GPT-4.5 could therefore not only become an indispensable tool in a wide range of application areas, but also represent a significant milestone on the path towards general artificial intelligence, the benefits and acceptance of which in society could increase massively as a result of these advances.

GPT-4.5 was developed using a combination of different methods, with unsupervised learning playing a key role. The model processed huge amounts of text data from the internet and other sources without being given specific labels or instructions. Using this method, GPT-4.5 independently recognized patterns, structures and relationships in language and context, which significantly improved its capabilities and enabled it to gain a deep understanding. In addition, GPT-4.5 was then further developed through supervised fine-tuning. This involved giving it specific, human-generated examples to train it to perform certain tasks precisely and reliably. Another important step was reinforcement learning from human feedback (RLHF), in which human reviewers evaluated the model's responses and provided feedback. This method helped GPT-4.5 to better align its responses with human needs and expectations and to meet ethical and quality standards. What is particularly outstanding about GPT-4.5's unsupervised learning is that it was used on an unprecedented scale, achieving an even broader and deeper knowledge base. Through these innovations in training scope and methodology, GPT-4.5 was able to generate precise, creative and contextualized responses and communicate in a much more human-like way.

The Controversy

The release of GPT-4.5 has caused mixed reactions in the community. A key point of criticism is that the model does not fully meet the high expectations despite the hype generated in advance. In particular, tests such as those conducted by Andrej Karpathy showed that users preferred the GPT-4o answers to GPT-4.5 in four out of five cases. Although GPT-4.5 was advertised as more creative and emotionally intelligent, these improvements were not always reflected in user preferences. Some users even reported poorer performance in creative writing compared to previous models.

Another aspect that contributes to the disappointment is the pricing. GPT-4.5 is considerably more expensive than its predecessors, which is a hurdle for professional users in particular. OpenAI justifies the high costs with the enormous computing effort required by the model. The size of the model presumably also means that its performance is unexpectedly slow. This could be due to the size and complexity of GPT-4.5, which leads to longer response times.

Although GPT-4.5 shows recognizable progress in certain areas, the comprehensive improvements that many had hoped for have not materialized. Sam Altman himself contributed significantly to this disappointment, as he had considerably raised expectations around the release of GPT-4.5 - known internally as Project “Orion” - by making cryptic hints over a long period of time. The highlight was a statement published by Altman on X, in which he personally described GPT-4.5 as the first real “feel-the-AGI” moment. As CEO of OpenAI and former president of Y-Combinator, Altman is undoubtedly aware of the enormous power and reach of his words. But it is precisely this power that can also turn against him, like a boomerang, if reality falls short of his lofty expectations.

The combination of limited progress in logical thinking, high costs and performance problems contributes to disappointment in the community.

Why Has GPT-4.5 Been Released Now?

In the discussion about GPT-4.5, it is often forgotten which target group this model is actually intended for. In my view, GPT-4.5 is not primarily aimed at those experienced users who have to master complex programming tasks or carry out particularly demanding analyses on a daily basis, but rather at the broad mass of so-called “casual users”. These are users who are primarily looking for support with everyday tasks - such as writing emails, summarizing articles or quickly answering everyday questions. It is precisely in these areas, where particularly computationally and analytically intensive reasoning models do not offer any substantial added value, that GPT-4.5 really comes into its own.

With GPT-4.5, OpenAI essentially replaces the basic GPT-4o model, which was widely used, particularly in the free tier. From a perspective, GPT-4.5 thus represents the transition to GPT-5, which should be usable in future without restrictions in terms of rate limits. In this sense, GPT-4.5 forms the bridge between the model generations and becomes an everyday companion for creative, communicative and practical issues. And in this role, GPT-4.5 undoubtedly fulfills its purpose.

Looking at the benchmarks, it is clear that GPT-4.5 is in no way inferior to its predecessor. Nevertheless, the model suffers from the enormous success and the associated expectations that have become firmly associated with the ChatGPT brand. For many people, ChatGPT is synonymous with artificial intelligence, just as “googling” has long since become synonymous with internet searches. This success, supported by the hype around Artificial General Intelligence, which was intensively fueled by OpenAI itself, has enormously increased expectations towards new models such as GPT-4.5. It was almost impossible to fully meet these expectations.

GPT-4.5 is undoubtedly a good model, but for most users it does not fulfill the high, sometimes unrealistic expectations that they associate with the term AGI. This also raises the question of why OpenAI released GPT-4.5 at all when its successor, GPT-5, is due to be released in just a few months. GPT-5 is regarded within the community as the model that could come closest to the long-awaited ideal of an AGI. This is because GPT-5 combines reasoning and non-reasoning components in a single model for the first time, which independently decides how intensively it should react to a query (so-called “inference scaling”).

The reason for the release of GPT-4.5 is probably the increasing competition on the market. More and better models are entering the market in a short space of time - be it “Le Chat” from Mistral, “Grok” from xAI, “Claude” from Anthropic or “Llama” from Meta. Even China, despite technological embargoes, is now competing with DeepSeek r1 at a level comparable to OpenAI's GPT-4o. Particularly noteworthy is also xAI's “Grok 3”, which is able to take on various roles so convincingly through customization that it appears almost human. In short: OpenAI is under massive pressure.

GPT-4.5 is therefore a strategic response to retain the broad mass market and satisfy the “casual user”. It is intended to prevent users, especially paying subscribers in the Plus tier, from migrating to the competition before the release of GPT-5. But this is also the core problem: GPT-4.5 suffers from the extremely high expectations that OpenAI itself has created. If the same model had been developed by a small start-up, it would undoubtedly have been considered an outstanding success. However, as it comes from the established industry leader, it is in danger of failing due to the weight of its own past and the enormous expectations.

Nevertheless, the progress made in terms of reducing hallucinations, improving context sensitivity and increasing creativity is remarkable - and this is exactly what I would like to emphasize. GPT-4.5 is by no means a bad model. It is good, even extremely good. The real problem lies in the expectations that were placed on the new model in advance. These expectations were simply too high, while at the same time improvements were introduced that were not necessarily expected or hoped for. Looking back, I still consider GPT-4.5 to be an important release, possibly even a milestone. However, if this release has shown us anything, it is how powerful words can be - and that some should be more careful not to use this power carelessly or excessively in future releases. Otherwise the boomerang will inevitably strike back.

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