Artificial Intelligence

DeepSeek: what it is, how it works, models, app and differences from ChatGPT

DeepSeek is the artificial intelligence developed by the Chinese company of the same name: but what is it, how does it work and how do you use it? In this guide we look at how to use DeepSeek for free, how its models work, what tools it offers and how to access its apps and API. We will also see what DeepSeek can do, the main differences from ChatGPT, and what to consider regarding privacy, security and professional use.

logo deepseek in liquid glass, copertina magazine digitale di Bliss

DeepSeek is a generative artificial intelligence platform developed by the Chinese company Hangzhou DeepSeek Artificial Intelligence. It very quickly became one of the most significant names in the AI sector, thanks to language models geared towards reasoning, programming, text processing and complex tasks.

Today, however, simply referring to “DeepSeek R1” or “DeepSeek V3” is no longer enough to describe the service. In 2026 the ecosystem evolved into the DeepSeek-V4 family and, more recently, DeepSeek-V4.1-Flash: a model that also integrates multimodal capabilities and is now the platform’s reference model.

DeepSeek can be used via the website, the official application and the developer APIs. A particularly interesting project for the way it combines Mixture-of-Experts models, reasoning, computational efficiency, open-weight development and integration with AI-based tools and workflows.

DeepSeek logo

What is DeepSeek?

DeepSeek is a generative AI system based on large language models, designed to understand natural-language requests and produce answers consistent with the context of the conversation.

In practice, DeepSeek can be used as a chatbot to write and rewrite texts, explain concepts, analyse information, work on code, solve mathematical problems and tackle tasks that require reasoning.

The platform therefore does not equate to a single model. The name DeepSeek identifies an ecosystem made up of different models, services and tools, available in different ways depending on use.

This distinction matters because much of the information still found online describes DeepSeek solely through R1, the reasoning model that brought the project to international prominence in 2025. R1 remains a milestone in DeepSeek’s history, but on its own it no longer represents the current state of the platform. In 2026 the line moved on to the V4 generation and subsequently V4.1.

Is DeepSeek a chatbot or an artificial intelligence model?

Both definitions can be correct, but they refer to two different levels.

DeepSeek is the name of the project and the platform; the DeepSeek chatbot is the interface through which a user can interact with the models; DeepSeek-V4.1-Flash, on the other hand, is one of the models powering the platform’s features.

The same technology can also be accessed via API within applications, software and systems developed by third parties.

It is therefore more accurate to think of DeepSeek as an AI ecosystem than as a simple chat application.

How does DeepSeek work?

From the user’s point of view, it works very simply: you enter a request, commonly called a prompt, and the model generates a response based on the information in the request and the available context.

Behind this interaction, however, lies a far more complex system.

Language models are trained on large amounts of data and learn to represent statistical relationships and linguistic structures. During use, the model processes the text it receives and determines which response to generate, progressively producing a sequence of tokens.

In reasoning-oriented models, the process can be further optimised to tackle problems that require multiple logical steps. This is one of the reasons DeepSeek has drawn particular attention in mathematics, programming and complex problem-solving.

Mixture-of-Experts: why it matters

One of the technological features associated with the DeepSeek family is the Mixture-of-Experts (MoE) architecture.

In a model of this type, not all available parameters need to be used to the same extent for every single request. The system can activate the subset of experts best suited to the task at hand.

The aim is to achieve a more efficient ratio between model capability and the computational resources used.

This is particularly important when discussing DeepSeek, because one of the project’s central issues is precisely efficiency: capable models at reduced inference and training costs.

Does DeepSeek really reason?

The term “reasoning” should be used with care.

When we talk about reasoning in an AI model, it does not mean that the system is conscious or reasons like a person. It means that its architecture and training are designed to tackle certain problems through more elaborate computational processes, which are particularly useful for maths, code, logic and multi-step tasks.

DeepSeek-R1 played a significant role in precisely this area. DeepSeek presented the model as a reasoning-focused system and benchmarked it against competing models on mathematics, programming and reasoning tasks.

The next generation, however, broadened the objective: the current DeepSeek-V4.1-Flash combines general capabilities, reasoning, agentic tasks and multimodal visual understanding.

DeepSeek V4.1 Flash: the current model

In September 2026, DeepSeek unveiled DeepSeek-V4.1-Flash, a model built on the new V4.1 architecture.

According to the official documentation, V4.1-Flash is a 552-billion-parameter Mixture-of-Experts model with a Causal Encoder–Decoder architecture that activates 8 billion parameters in the input phase and 16 billion in the output phase. The model also offers native visual understanding.

DeepSeek has worked on architectural efficiency, memory management and performance in agentic workflows. The company itself states that V4.1-Flash requires significantly less HBM memory and SSD space for the KV cache than the previous generation.

The model is available through the DeepSeek API under the name deepseek-flash.

The platform has also changed the role of the earlier V4 Flash models: the previous versions have been retired and requests addressed to their names are routed to V4.1-Flash.

This means that an up-to-date article on DeepSeek should avoid presenting V3, R1 or V4 Flash as if they were necessarily still the main model used by the service.

What are the DeepSeek models?

DeepSeek’s recent history can be understood through a few main generations.

DeepSeek V3

V3 was one of the models that helped bring the project international recognition, chiefly for the balance it struck between model capability, architecture and usage costs.

DeepSeek R1

R1 is the model that made DeepSeek particularly famous in 2025, and which we covered in the retrospective Why DeepSeek stopped no one, analysing the R1 case and the Jevons Paradox.  

Its distinctive feature was its focus on reasoning. DeepSeek published the model and the related technical work, also making available distilled models derived from R1.

DeepSeek V4

In 2026 DeepSeek introduced the V4 family, initially with V4-Pro and V4-Flash.

One of the distinctive features of the V4 generation was support for a context window of up to 1 million tokens, together with reasoning and non-reasoning modes and features designed for agentic tasks as well.

DeepSeek V4.1 Flash

V4.1-Flash represents the next evolution of the family.

In addition to its language and reasoning performance, it introduces native visual understanding, enabling the model to work with visual content too. DeepSeek presented it as a faster, more efficient model suited to complex workflows.

For this reason, when searching for “DeepSeek V4” today, it is important to check the date of the source: the model has evolved very rapidly, and information that was correct at the time of publication may have become obsolete within a few months.

What you can do with DeepSeek

DeepSeek can be used for many of the tasks we normally associate with generative AI assistants.

Cosa si può fare con DeepSeek

Produrre e trasformare testo

Il risultato dipende dal contesto fornito: una richiesta generica produce un risultato generico.

  • Creare una prima bozza
  • Riscrivere un testo
  • Correggere grammatica e sintassi
  • Sintetizzare documenti
  • Cambiare il tono
  • Generare idee
  • Organizzare informazioni
  • Costruire strutture per articoli e documenti

Studiare e comprendere

Strumento di supporto, non fonte definitiva: una risposta ben formulata può comunque contenere errori.

  • Spiegare un concetto con parole semplici
  • Proporre esempi
  • Confrontare teorie
  • Costruire esercizi
  • Individuare i passaggi di un problema

Codice

Per uso professionale il codice va verificato, eseguito in ambienti controllati e sottoposto a revisione.

  • Generare codice
  • Spiegare funzioni
  • Individuare errori
  • Proporre refactoring
  • Creare test

Ragionamento su problemi complessi

I modelli orientati al reasoning aiutano quando servono più passaggi logici, ma il ragionamento prodotto non garantisce la correttezza.

  • Risolvere problemi matematici
  • Analizzare un algoritmo
  • Scomporre una situazione in passaggi

Oltre il testo

Con V4.1-Flash la comprensione visiva è parte nativa del modello.

  • Interpretare immagini
  • Leggere documenti
  • Analizzare contenuti visivi

Le funzionalità effettivamente disponibili dipendono dal modello e dall'interfaccia utilizzata.

Writing and rewriting texts

It can help produce a first draft, rewrite a text, correct grammar and syntax, summarise documents, change the tone of a piece of content, generate ideas, organise information and create outlines for articles or documents.

The quality of the output, however, depends on the context provided. A generic request generally produces a more generic result than a prompt that specifies the objective, audience, tone, constraints and information to be used.

Studying and understanding complex topics

DeepSeek can be used as a study aid.

It can explain a concept in simple terms, offer examples, compare theories, build exercises or help identify the steps of a problem.

It should not, however, automatically be considered a definitive source. A well-worded answer can still contain errors.

Programming and code

Programming is one of the areas in which DeepSeek models have attracted particular attention.

They can be used to generate code, explain functions, identify potential bugs, suggest refactoring, create tests and assist in software development.

For professional work, generated code must still be checked, run in controlled environments and put through standard review processes.

Mathematics and complex problems

Reasoning-oriented models can be useful when a request involves multiple logical steps.

You can ask DeepSeek to solve a mathematical problem, analyse an algorithm or break down a complex situation into successive steps.

Here too, however, the reasoning produced by the model is no absolute guarantee of accuracy.

Analysis of images and visual content

With V4.1-Flash, visual understanding has become a native part of the model. This extends its possible uses beyond text alone and makes it possible to work with information contained in images.

Depending on the features actually available in the interface used, applications may include the interpretation of images, documents and visual content.

DeepSeek in Italian: does it work?

Yes. DeepSeek can also be used in Italian.

You can write prompts in Italian and ask for the answer to be produced in the same language. This makes DeepSeek accessible even to those unfamiliar with technical English.

Quality may nonetheless vary depending on the type of request, the model used and the complexity of the task. For professional content, it is always advisable to check terminology, data and wording before publication.

User using DeepSeek on a smartphone and computer in China
DeepSeek can be used through the web interface and the mobile app, as well as via API for integration into software and professional workflows.

How to use DeepSeek online

Using DeepSeek online is relatively straightforward.

The official platform provides the web service and allows users to interact directly with the chatbot. The official website also offers access to the app, the APIs and the other tools in the DeepSeek ecosystem.

The workflow is that of a typical AI assistant:

  1. you access the official platform;
  2. log in when prompted;
  3. a conversation is opened;
  4. enter the prompt;
  5. the answer is analysed;
  6. continue with any follow-up requests.

The quality of the output depends heavily on how the request is phrased.

How to write a good prompt for DeepSeek

A good prompt must be specific.

It is useful to specify:

  • what you want to achieve;
  • who the output is intended for;
  • which format to use;
  • what information to consider;
  • which constraints to respect;
  • what tone to adopt;
  • which elements to avoid.

DeepSeek app: how to use it on smartphone and tablet

DeepSeek has an official mobile application.

The platform currently lists the app as available for iOS and Android and also offers a desktop version called DeepSeek Harness for macOS and Windows.

The app lets you use the AI assistant directly from a smartphone or tablet, retaining the conversational experience of the web version.

It is important, especially when searching for “DeepSeek app”, to make sure you download the official application and not one of the many third-party applications that use similar names or images.

DeepSeek itself recommends using official channels for downloads.

Is DeepSeek free?

DeepSeek offers free access to its assistant through the channels intended for end users, while API usage follows a pricing model based on the tokens consumed.

This means distinguishing between use of the chatbot and professional use via API.

For developers, the DeepSeek API allows the models to be integrated into their own software and supports formats compatible with APIs used in the OpenAI and Anthropic ecosystem. The current documentation lists deepseek-flash and deepseek-v4-pro among the available API models.

Moreover, price should not be assessed solely on the cost per token. In a real project, performance, latency, request volume, infrastructure, memory management, output quality and integration costs also count.

DeepSeek

Chinese company of the same name

Founded with a strong focus on language model research. Its orientation is towards reasoning, efficiency and making weights available to the community.

  • Reasoning
  • Efficiency
  • Open-weight models
  • Watch the costs

ChatGPT

OpenAI

It integrates a very broad range of capabilities, tools and services. The focus is on an extensive ecosystem built around the assistant.

  • Breadth of features
  • Built-in tools
  • Service ecosystem
  • Many models available

DeepSeek vs ChatGPT: what is the difference?

DeepSeek and ChatGPT belong to the same broad category of generative AI assistants, but they are not the same product and do not use the same models.

The most evident difference concerns the technological and commercial ecosystem.

ChatGPT (which we have covered in a dedicated article) is the assistant developed by OpenAI and brings together a very wide range of capabilities, tools and services.

DeepSeek, by contrast, is the ecosystem developed by the Chinese company of the same name, built with a strong focus on language model research, reasoning, efficiency and the availability of open-weight models.

There is therefore no universal answer to the question “is DeepSeek or ChatGPT better?”.

The choice depends on the task.

For example, one user might prefer a particular service for writing, another for programming, and yet another for API integrations or for the option of using models whose weights are available to the community.

Technical comparisons, too, should be made between specific model versions, not between the generic names of platforms. Simply saying “DeepSeek versus ChatGPT” without specifying the model, date and task makes the comparison of little value.

Is DeepSeek better than ChatGPT?

There is no universally valid answer.

DeepSeek has become a major competitor in generative AI mainly thanks to its combination of reasoning, efficient model development, open weights in some families and attention to cost.

ChatGPT, by contrast, belongs to a different ecosystem, with a very broad set of models, tools and features.

The right comparison should therefore start from the question:

“Which system is best suited to this specific task?”

For writing, programming, research, document analysis, images, automation or software development, performance may vary depending on the model used, the configuration and the type of task.

This is why comparisons based on a single benchmark or a single personal experience are useful, but not sufficient for choosing a platform for professional use. The same applies to Google’s Gemini and Anthropic’s Claude.

Liang Wenfeng, founder of DeepSeek, speaking at a public event
Liang Wenfeng, founder of DeepSeek, built the project around model research, computational efficiency and the development of architectures capable of competing with far more expensive systems.

Is DeepSeek open source?

Here too, it is important to use precise terminology.

In the AI debate, DeepSeek is often described as “open source”. The project has indeed published models and weights under licences that permit certain uses, and has contributed to making technologies accessible to the community.

For example, DeepSeek-R1 was released under the MIT licence, and DeepSeek has also made available distilled models derived from R1.

However, an open-weight model does not automatically mean that every element of the entire DeepSeek system is open.

The model, the training data, the infrastructure, the cloud service, the application and the APIs are distinct components.

This distinction matters above all for companies and developers evaluating DeepSeek for their own deployment.

DeepSeek for businesses and developers

Professional interest in DeepSeek is not limited to chat.

The APIs allow the models to be integrated into software applications and workflows. The official documentation also indicates compatibility with API formats used in the OpenAI and Anthropic ecosystem.

This opens up scenarios such as internal assistants, automated document analysis, text generation and transformation, software development support, information classification, automation of repetitive tasks, agentic workflows and custom AI applications.

For a company, however, the choice of a model should not be determined solely by its ability to produce a good answer.

Before adopting it, organisations need to assess at least the data processed, privacy, security, retention arrangements, regulatory requirements, reliability, output control, costs, integration options and AI governance.

DeepSeek and privacy: what data is processed?

The privacy question is particularly important for anyone using DeepSeek with personal information, company documents or confidential data.

DeepSeek’s privacy policy, updated in April 2026, states that the service may collect, among other data, account information, prompts, uploaded files, photos, feedback, chat history, device data, network information, logs and an approximate location derived from the IP address.

The same privacy policy also states that personal data may be stored and processed in the People’s Republic of China and that data may be shared with service providers to the extent necessary to provide, support and develop the service.

This does not mean that DeepSeek should automatically be considered unsafe. It does mean, however, that the type of data entered into the service must be assessed carefully.

A precautionary rule applies to any generative chatbot: avoid entering confidential information, credentials, trade secrets or unnecessary personal data without first checking the contractual terms, settings and data processing.

The Italian privacy case

The DeepSeek question has been particularly significant in Italy.

On 30 January 2025, the Italian Data Protection Authority (Garante per la protezione dei dati personali) ordered, with immediate effect, a restriction on the processing of Italian users’ data by the companies providing the DeepSeek service, and simultaneously opened an investigation.

The measure stemmed from shortcomings identified by the Authority in the information provided by the companies on the processing of personal data and on the applicability of European legislation.

This episode matters for understanding a broader point: choosing an artificial intelligence system for professional use is not just a matter of assessing the quality of its answers.

Privacy, international data transfers, security and compliance must all form part of the overall assessment.

What are DeepSeek’s limitations?

Like any generative model, DeepSeek is not infallible.

An answer may be incomplete, inaccurate or out of date. It may be phrased with excessive confidence or based on a misreading of the request. This phenomenon is often associated with generative artificial intelligence hallucinations.

The issue is particularly important when the content produced concerns legal, financial, medical, technical or other information where an error can have significant consequences.

A model’s ability to reason or produce convincing answers does not remove the need for verification.

Can DeepSeek be wrong even when it seems confident?

The answer is: of course. One of the most insidious characteristics of language models is precisely their ability to produce fluent, persuasive answers even when the content is incorrect.

Building housing DeepSeek’s headquarters in Hangzhou, China
Hangzhou, China. DeepSeek is headquartered in the city that has become one of the most important hubs of China’s technology industry.

DeepSeek and security

Security must be assessed on several levels.

There is the security of the application, of the infrastructure and of the API and, above all, the security linked to how users actually use the system.

A chatbot connected to company data can become a vulnerable point if documents are uploaded without a proper internal policy.

Likewise, the introduction of agentic AI systems increases the importance of controls: a system that does more than generate text, and can use tools, process information or carry out operations, requires more rigorous governance.

The growing capability of agentic models therefore makes it necessary to distinguish between AI used as an assistant and AI embedded in operational processes.

DeepSeek V4.1 Flash and multimodality

One of the most interesting developments of the V4.1 generation is multimodality.

DeepSeek-V4.1-Flash has native visual understanding. This means the model is not designed solely to process text: it can also interpret visual information.

Multimodality broadens the range of use cases for artificial intelligence.

A model capable of combining text and images can be used, for example, to analyse visual documents, interpret screenshots, understand charts or support workflows in which textual and visual information must be considered together.

The actual functionality available to the user, however, depends on the interface and product through which the model is accessed.

DeepSeek for research and everyday work

The value of an AI assistant depends not only on the model, but on how it is integrated into the work process.

For everyday tasks, it can be used to turn unstructured information into more organised content, create first drafts, summarise material, weigh up alternatives or speed up repetitive tasks.

For example, a professional could give DeepSeek a set of notes and ask it to:

  1. identify the main concepts;
  2. order them;
  3. highlight any contradictions;
  4. turn them into a structure;
  5. produce a first draft;
  6. indicate which information requires verification.

In this scenario AI does not necessarily replace the professional: it reduces mechanical work and leaves the person with the most important part, namely oversight, judgement and decision.

DeepSeek: why it has become important in the AI sector

DeepSeek’s importance stems from the way it has shifted attention to some fundamental questions in artificial intelligence, such as the cost of developing advanced models, architectural efficiency, the role of open-weight models, the importance of reasoning, and the speed at which the competitive AI landscape can change.

The release of R1 in 2025 had already shown how quickly a new model could enter into competition with the most established systems. The subsequent evolution towards V4 and V4.1 also shows that the project did not stop at a single reasoning model.

How to evaluate DeepSeek before using it

For a private user, it may be enough to try it directly and see whether it meets their needs.

For a company, however, a more structured process is advisable.

Before integrating DeepSeek into professional work, it is worth checking:

1. The use case.
What problem should the AI solve? Generating content, analysing data, programming, classifying documents or automating a process?

2. The model.
Not all models are designed for the same type of task.

3. The quality of the output.
Answers must be tested on real cases, not just on demonstration examples.

4. The data.
You need to know what information is sent to the service and how it is processed.

5. Security.
Confidential documents and sensitive data require specific controls.

6. Costs.
For use via API, consumption, request frequency and infrastructure must be taken into account.

7. Governance.
It is necessary to establish who can use AI, with what data and for which tasks.

8. Human oversight.
A review process must be in place for outputs that affect important decisions.

DeepSeek: it is not just about the chatbot

Perhaps DeepSeek’s most significant evolution lies precisely in moving beyond the idea of the chatbot as a mere tool for asking questions.

The trajectory of the latest models is towards systems capable of handling long contexts, using tools, working with code, interpreting visual content and taking part in more complex workflows.

DeepSeek’s API documentation already shows integration geared towards development systems and agents, while the current V4.1-Flash has been designed with particular attention to agentic tasks.

This is why DeepSeek should be seen above all as an evolving technology platform, not simply as “the Chinese alternative to ChatGPT”.

DeepSeek beyond the chatbot

DeepSeek is a generative artificial intelligence platform that develops and distributes language models geared towards conversation, reasoning, programming, analysis and increasingly complex tasks.

Its path has taken in models such as V3 and R1, reached the V4 family and, in September 2026, arrived at DeepSeek-V4.1-Flash, which also introduces native visual understanding and a new architecture geared towards efficiency and performance.

It can be used online, through mobile apps and via API. For developers, it is an attractive option for integrating generative models into custom software and workflows.

For Italian users, however, use must be accompanied by particular attention to privacy and data management, not least in light of the events involving the service and the Italian Data Protection Authority (Garante) in 2025.

The question to ask before using it should therefore be: “which tasks is it genuinely suited to, and under what conditions can I use it?”.

As with any artificial intelligence system, value does not depend solely on the power of the model. It depends on the quality of the instructions, the quality of the data provided, the ability to verify the answers and, above all, the way the technology is embedded in day-to-day work.

Domande frequenti

Can DeepSeek be used in Italy?

The service may be technically accessible, but in Italy it remains subject to the Garante Privacy ruling of 30 January 2025. The Authority declared the processing of personal data carried out within the DeepSeek service unlawful and ordered the definitive restriction of processing activities concerning data subjects located in Italy. For this reason, particularly in a professional context, DeepSeek should not be regarded as a service usable in Italy without also assessing privacy and compliance aspects.

Is DeepSeek free?

Yes. DeepSeek offers end users free access to its assistant. API usage, on the other hand, follows a pay-as-you-go model based on the tokens processed. Terms and prices may change over time, so for professional use it is advisable always to check the latest official documentation.

Is DeepSeek Chinese?

Yes. DeepSeek is developed by Hangzhou DeepSeek Artificial Intelligence Co., Ltd., a company based in the People’s Republic of China. This is especially relevant for companies and professionals who need to assess where data is processed and stored and which rules apply to its use.

Is DeepSeek open source?

Not entirely. DeepSeek has released some models, code and weights under licences that permit their use and modification; DeepSeek-R1, for example, was distributed under the MIT licence. This does not mean, however, that the entire DeepSeek ecosystem, including apps, infrastructure, training data and cloud services, is fully open source.

Is DeepSeek better than ChatGPT?

There is no universally valid answer. DeepSeek and ChatGPT belong to different ecosystems and can offer different advantages depending on the task. The most useful comparison must consider the specific model, the type of task, the quality of the output, the tools available, costs, privacy and integration requirements.

What is the latest DeepSeek model?

In 2026 DeepSeek took its model family beyond R1 and V3, developing the V4 generation and subsequently V4.1. Among the most recent models is DeepSeek-V4.1-Flash, designed to combine reasoning, computational efficiency, agentic tasks and native visual understanding.

Fonti e riferimenti
  1. DeepSeek, Informativa sulla Privacy di DeepSeek
  2. DeepSeek, Condizioni Generali di DeepSeek
  3. DeepSeek-AI, DeepSeek-R1
  4. Garante per la protezione dei dati personali, Provvedimento del 30 gennaio 2025 [10098477]
  5. Garante per la protezione dei dati personali, Intelligenza artificiale: il Garante privacy blocca DeepSeek
  6. Aggiungerei anche queste due, perché utili per la parte tecnica del tuo articolo
  7. DeepSeek-AI, DeepSeek-R1 License
  8. DeepSeek-AI, DeepSeek-R1 README
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