Maybe due to the disappointing outcomes, Altman had beforehand written that GPT-4.5 would be the final of OpenAI’s conventional AI fashions, with GPT-5 deliberate to be a dynamic mixture of “non-reasoning” LLMs and simulated reasoning fashions like o3.
A stratospheric value and a tech dead-end
And about that value—it is a doozy. GPT-4.5 prices $75 per million enter tokens and $150 per million output tokens by the API, in comparison with GPT-4o’s $2.50 per million enter tokens and $10 per million output tokens. (Tokens are chunks of information utilized by AI fashions for processing). For builders utilizing OpenAI fashions, this pricing makes GPT-4.5 impractical for a lot of purposes the place GPT-4o already performs adequately.
Against this, OpenAI’s flagship reasoning mannequin, o1 professional, prices $15 per million enter tokens and $60 per million output tokens—considerably lower than GPT-4.5 regardless of providing specialised simulated reasoning capabilities. Much more putting, the o3-mini mannequin prices simply $1.10 per million enter tokens and $4.40 per million output tokens, making it cheaper than even GPT-4o whereas offering a lot stronger efficiency on particular duties.
OpenAI has probably identified about diminishing returns in coaching LLMs for a while. Because of this, the corporate spent most of final 12 months engaged on simulated reasoning fashions like o1 and o3, which use a unique inference-time (runtime) strategy to bettering efficiency as an alternative of throwing ever-larger quantities of coaching information at GPT-style AI fashions.

Whereas this looks like dangerous information for OpenAI within the brief time period, competitors is flourishing within the AI market. Anthropic’s Claude 3.7 Sonnet has demonstrated vastly higher efficiency than GPT-4.5, with a reportedly extra environment friendly structure. It is price noting that Claude 3.7 Sonnet is probably going a system of AI fashions working collectively behind the scenes, though Anthropic has not supplied particulars about its structure.
For now, evidently GPT-4.5 often is the final of its sort—a technological dead-end for an unsupervised studying strategy that has paved the way in which for brand spanking new architectures in AI fashions, akin to o3’s inference-time reasoning and maybe even one thing extra novel, like diffusion-based fashions. Solely time will inform how issues find yourself.
GPT-4.5 is now obtainable to ChatGPT Professional subscribers, with rollout to Plus and Staff subscribers deliberate for subsequent week, adopted by Enterprise and Training clients the week after. Builders can entry it by OpenAI’s varied APIs on paid tiers, although the corporate is unsure about its long-term availability.
Maybe due to the disappointing outcomes, Altman had beforehand written that GPT-4.5 would be the final of OpenAI’s conventional AI fashions, with GPT-5 deliberate to be a dynamic mixture of “non-reasoning” LLMs and simulated reasoning fashions like o3.
A stratospheric value and a tech dead-end
And about that value—it is a doozy. GPT-4.5 prices $75 per million enter tokens and $150 per million output tokens by the API, in comparison with GPT-4o’s $2.50 per million enter tokens and $10 per million output tokens. (Tokens are chunks of information utilized by AI fashions for processing). For builders utilizing OpenAI fashions, this pricing makes GPT-4.5 impractical for a lot of purposes the place GPT-4o already performs adequately.
Against this, OpenAI’s flagship reasoning mannequin, o1 professional, prices $15 per million enter tokens and $60 per million output tokens—considerably lower than GPT-4.5 regardless of providing specialised simulated reasoning capabilities. Much more putting, the o3-mini mannequin prices simply $1.10 per million enter tokens and $4.40 per million output tokens, making it cheaper than even GPT-4o whereas offering a lot stronger efficiency on particular duties.
OpenAI has probably identified about diminishing returns in coaching LLMs for a while. Because of this, the corporate spent most of final 12 months engaged on simulated reasoning fashions like o1 and o3, which use a unique inference-time (runtime) strategy to bettering efficiency as an alternative of throwing ever-larger quantities of coaching information at GPT-style AI fashions.

Whereas this looks like dangerous information for OpenAI within the brief time period, competitors is flourishing within the AI market. Anthropic’s Claude 3.7 Sonnet has demonstrated vastly higher efficiency than GPT-4.5, with a reportedly extra environment friendly structure. It is price noting that Claude 3.7 Sonnet is probably going a system of AI fashions working collectively behind the scenes, though Anthropic has not supplied particulars about its structure.
For now, evidently GPT-4.5 often is the final of its sort—a technological dead-end for an unsupervised studying strategy that has paved the way in which for brand spanking new architectures in AI fashions, akin to o3’s inference-time reasoning and maybe even one thing extra novel, like diffusion-based fashions. Solely time will inform how issues find yourself.
GPT-4.5 is now obtainable to ChatGPT Professional subscribers, with rollout to Plus and Staff subscribers deliberate for subsequent week, adopted by Enterprise and Training clients the week after. Builders can entry it by OpenAI’s varied APIs on paid tiers, although the corporate is unsure about its long-term availability.