ChatGPT-5: Finally Available, a Turning Point for AI?

For several years now, conversational artificial intelligence has established itself in all fields: from writing to programming, as well as in healthcare and education. This text and multimodal assistance generator from OpenAI has captured worldwide attention. While ChatGPT-4 (2023) had already set new standards in understanding and reasoning, this new version claims to be the company’s biggest leap forward to date. According to OpenAI, GPT-5 is its “most intelligent, fastest, and most useful” model ever. The arrival of ChatGPT-5 in 2025 was highly anticipated by industry experts, but what are its real contributions? Does this new version mark a true breakthrough, or is it merely an incremental improvement?

Table of contents:

1. ChatGPT-5: evolution or revolution?
2. GPT-4 vs GPT-5 comparison: what’s different?
3. Limitations and open questions
4. Some examples of use by sector
5. Impact and adoption in Switzerland

ChatGPT-5: evolution or revolution?

ChatGPT-5 stands out from its predecessors not simply through improved performance, but through real advances in contextual understanding, personalization, and integration into workflows. This version pushes AI toward an even more intuitive use, accessible to all types of users, without requiring technical settings or complex model selection.

OpenAI presents version 5 as a “unified” model, capable of automatically adapting to the level of complexity and specialization required for each request, further democratizing access to advanced artificial intelligence.

GPT-4 vs GPT-5 comparison: what’s different?

Performance and accuracy

One of the major criticisms of earlier versions of ChatGPT was their tendency toward “hallucinations” — the generation of incorrect or unverified information. GPT-5 takes a big step forward with a dramatic reduction in such errors: OpenAI reports up to 45% fewer mistakes compared to GPT-4o, and an 80% reduction in complex reasoning errors compared to GPT-4. (fortune.com and cbsnews.com)

“GPT-5’s deep thinking mode bridges the gap to expert-level problem solving… Up to 80% fewer factual errors during reasoning, with major advances in healthcare, mathematics, and coding tests.” In internal tests, GPT-5 outperformed GPT-4/4o by 15–30% on complex tasks, with enhanced reliability in coding and scientific queries. (getpassionfruit.com)

Architecture and technical capabilities

GPT-5 pushes the limits of its predecessor. While GPT-4 capped at around 170 billion parameters, GPT-5 potentially exceeds the 500 billion mark. This scale-up goes hand in hand with an architectural overhaul: the underlying technology combines graph neural networks with enhanced contextual attention.

The model now supports up to 1 million context tokens in certain cases, compared to 128,000 for GPT-4o. This means GPT-5 can remember, reason, and connect much larger volumes of data or text, revolutionizing long-tail applications (legal case analysis, scientific research, etc.).

Speed, efficiency, and personalization

GPT-5 is not only faster for simple tasks; it can also activate “deep” reasoning for complex requests without human intervention. It can handle multi-step workflows reliably and quickly, whereas GPT-4 often required switching models or restarting the sequence.

In 2025, GPT-5 natively includes four personalities: Cynic, Robot, Listener, Nerd. This allows immediate adaptation of response style to the user or context — Swiss companies, for example, can obtain a more factual tone for financial analysis or a more empathetic tone for HR advice.

Context and hallucination management

The ability to work with very large volumes of context (files, conversations, research) enables ChatGPT-5 to deliver more accurate, less forgetful analyses, outperforming its main competitor, Claude Opus 4.1, on front-end or analytical tasks.

GPT-5 can assess its own confidence level: it can indicate when it does not have a reliable answer instead of producing an invented one. This is a crucial advancement for fields where reliability is essential, such as healthcare, law, or public administration.

Limitations and open questions

Cost and quotas: the free tier of GPT-5 is less generous than GPT-4’s (10 messages/day vs. 25 messages every three hours). The Pro version costs around $200/month, a prohibitive amount for many individuals or SMEs.

Still hallucinated content: although the factual error rate is decreasing, a risk remains. Users should verify sensitive information.

Moderate progress according to some experts: Reuters notes that anonymous testers believe the leap from GPT-4 to GPT-5 is less impressive than from GPT-3 to GPT-4 (reuters.comreuters.com). The media hype may therefore outweigh the actual gains.

Availability and privacy: integration with Google services raises data protection concerns, particularly in Europe. The Swiss regulatory framework for AI is still being developed, which may create uncertainty (swissinfo.ch).

Some examples of use by sector

Web development

For developers, GPT-5 becomes a coding partner: it can generate web applications, suggest fixes, or document code. A considerable time-saver and perfect for problem-solving. A true personal coding assistant.

Marketing and communication

Thanks to its new personalities and smoother writing, GPT-5 is better suited for marketing content generation. Fortune notes that the produced texts are more engaging than GPT-4’s (fortune.com). According to CorpIn, 65% of Swiss companies consider AI a strategic factor, but only a minority measure results precisely (corpin.ch).

Customer service and conversational agents

Auto-routing and the ability to integrate calendars pave the way for more autonomous conversational agents. GPT-5 can handle bookings, analyze emails, and extract relevant information.

Healthcare and biomedical research

GPT-5 can help interpret medical results, suggest questions to ask a doctor, or explain complex concepts. However, as CBS News and Fortune remind us, it does not replace a professional and should be used with caution (cbsnews.com).

Impact and adoption in Switzerland

According to a study cited by CorpIn, about 65% of Swiss companies have integrated AI into their long-term strategy, but only 13% set measurable goals and have real performance indicators (corpin.ch). This limited maturity leaves significant room for growth in the adoption of technologies like GPT-5. The same source highlights the growing importance of generative and multimodal models to personalize the customer experience and create new services.

Swiss companies show a certain caution toward AI compared to other countries. Swiss firms seem more wary of legal risks and data protection issues. This caution, combined with a consensus-driven culture, could slow rapid GPT-5 adoption but encourage more responsible deployments. SMEs can start with the free version, test limited use cases (content generation, internal assistance), and then evaluate paid plans.

Conclusion:

ChatGPT-5 marque un tournant majeur dans l’IA générative : la nouvelle architecture unifiée, la réduction drastique des hallucinations, la vitesse et surtout la capacité à s’adapter automatiquement font de cette version un allié incontournable des acteurs suisses, tous secteurs confondus. Les avancées ne sont pas seulement techniques elles sont centrées sur l’utilisateur, la transparence et l’efficacité. Reste à savoir quand sortira la prochaine version, ChatGPT-6, et quelles seront les nouvelles améliorations apportées.

FAQ

Quelles sont les principales différences entre GPT-4 et GPT-5 ?
GPT-5 apporte une meilleure compréhension contextuelle, un contexte mémoire élargi (jusqu’à 1 million de tokens dans certains cas), une forte réduction des erreurs factuelles et des capacités multimodales avancées. Il intègre aussi un système unifié qui adapte automatiquement la complexité des réponses.

GPT-5 est-il vraiment plus fiable que GPT-4 ?
Oui, mais pas infaillible. Les benchmarks montrent jusqu’à 80 % d’erreurs de raisonnement en moins sur certaines tâches, et une nette amélioration en mathématiques, santé et codage. Toutefois, des vérifications restent nécessaires pour les informations critiques.

ChatGPT-5 est-il accessible gratuitement ?
Une version gratuite existe, mais elle est limitée à 10 messages par jour. La version Pro (environ 200 $/mois) donne accès à plus de requêtes, aux modes avancés, et aux nouvelles fonctionnalités en priorité.

Comment GPT-5 protège-t-il mes données personnelles ?
OpenAI affirme ne pas utiliser les conversations des utilisateurs professionnels (via ChatGPT Enterprise ou Teams) pour l’entraînement. Les réglementations locales (RGPD, LPD suisse) imposent aussi des règles strictes, mais il reste important de ne pas partager d’informations sensibles.

Dans quels domaines GPT-5 peut-il être le plus utile ?
Il est performant dans le développement logiciel, l’analyse de données, la génération de contenus, le service client, et la recherche scientifique. Sa polyvalence multimodale ouvre aussi la voie à des usages en éducation, marketing, et assistance médicale (avec prudence).