Does turning off AI training also delete my old chats?

Not always. The CNIL says Gemini's activity setting can imply deletion of past conversations and disable future history, but other services may separate training controls from stored chat history.

What counts as sensitive data in a chatbot prompt?

The CNIL gives examples such as health information, political opinions, and religious or trade union information. Avoid sharing that kind of data unless the service clearly needs it for the task.

I do not have an account on a platform. Can my data still be involved?

Yes. The CNIL explains that chatbots may process personal data to keep a trace of a conversation even without account creation or directly identifying details.

Is a settings toggle the only way to object to data reuse?

No. The CNIL also lists form-based routes for some services, including Meta, WhatsApp, Gemini, and LinkedIn, which can be useful when you want to exercise your rights more formally.

Turn off AI chat history so your prompts stop training the model

Why this matters to you

Your 2-minute quick win

If you use ChatGPT, open your account settings, go to Gestion des données, then switch off Améliorer le modèle pour tous. Done correctly, the improvement option is no longer enabled in your settings, and your new chats are no longer opted in for model improvement from that account.

Most people treat AI chat like a private notebook. That is risky. The CNIL notes that many companies reuse user data to train AI models. That can include the prompts you type, the files you paste, and the chat history the service keeps.

This matters even if you never share a secret on purpose. People often paste drafts, complaints, CVs, travel plans, or work snippets into a chatbot. A single message can contain names, phone numbers, account details, or health information without you noticing.

It also matters because chat history and training are related, but not always the same thing. In some services, switching off the improvement setting stops reuse for training. In some services, turning off activity also removes saved history for future chats.

The safest habit is simple. Assume every prompt could be stored unless you turn that off. Then use the service settings to reduce both training use and retained history where the platform offers that control.

What the CNIL guidance shows

The CNIL lists exact controls for major platforms. Those controls sit in account settings, privacy menus, data control pages, or rights request forms. That means you do not need special software. You need a few minutes and the right menu path.

The same CNIL guidance also shows an important limit. Some platforms let you object through a settings toggle. Others also offer a form to exercise your rights. If you want the strongest privacy position, it is worth knowing both routes.

What you are protecting

You are protecting the content of your prompts first. Prompts often contain rough thoughts people would never publish elsewhere. Once saved in a chat log, that content can stay longer than you expect.

You are also protecting personal data inside the conversation. The CNIL explains that chatbot services often process personal data to keep a trace of the conversation, even when you do not create an account or directly provide clearly identifying details.

That means small fragments matter. A delivery problem, a booking reference, a draft complaint, or a copied email signature can identify you. Several harmless pieces together can reveal much more than one line alone.

You are protecting sensitive data too. The CNIL gives examples such as health information, political opinions, or religious and trade union information. That kind of data deserves extra care, because its treatment is in principle restricted under the GDPR.

You are also protecting your future self. Old chats are easy to forget. Months later, a saved conversation can still contain details about your finances, family, work, or travel plans.

Finally, you are protecting your expectations. Many people think deleting a browser tab ends the interaction. It does not. A service may still keep account activity, conversation history, or improvement settings unless you change them.

What it costs you if you skip this

The first cost is simple loss of control. If a chatbot keeps your history and uses it to improve models, you lose track of where your words may be reused inside that service.

The second cost is oversharing by habit. If the chat window always saves past conversations, you may start typing more freely over time. That leads to longer, messier, and more personal prompts.

The third cost is poor data hygiene. The CNIL says some chatbot data should be erased as soon as the conversation ends when longer retention is not needed. If you never touch the settings, you may accept more retention than your use case needs.

The fourth cost is exposure of sensitive data. The CNIL advises organisations to warn users not to communicate sensitive data and to purge such data immediately or at least regularly when its retention is not relevant. In plain terms, a chatbot is the wrong place for health details, political views, or similar intimate facts unless you truly need that service for that purpose.

The fifth cost is confusion. Many users think one privacy change fixes everything. It does not. A training toggle may stop model improvement while leaving old chat history visible. A history control may stop future saving while not affecting content already retained.

There is also a time cost later. If you only act after a problem, you may need to use a rights request form, gather screenshots, and explain your request to the provider. It is faster to set the options before you build months of history.

Step by step

Open the AI service you actually use most. Start with the account that contains your real prompts, not the one you rarely touch. Done correctly, you are signed in and looking at your own profile or settings area.
Look for the provider's data or privacy menu. The CNIL lists names such as Gestion des données, Confidentialité, Contrôle de données, Activité, or Préférences. Done correctly, you can see at least one setting that mentions model improvement, activity, data use, or training.
If you use ChatGPT, go to account settings, open Gestion des données, then find Améliorer le modèle pour tous and turn it off. Done correctly, the improvement setting is no longer enabled for your account.
If you use Microsoft Copilot, open account settings, go to Confidentialité, then disable Formation du modèle sur du texte and Formation du modèle sur la voix. Done correctly, both text and voice training options are off.
If you use Claude, open account settings, go to Confidentialité, then turn off Aider à améliorer Claude. Done correctly, the option is unchecked or disabled in that privacy screen.
If you use Gemini on the web, go to the Activité tab and choose Désactiver et supprimer l’activité under Activité dans les applications Gemini. On mobile, open your profile icon, then Activité dans les applications Gemini. Done correctly, activity is disabled, and the CNIL notes this can remove past conversations and disable conversation history for future chats.
If you use Grok directly, go to account Paramètres, then Contrôle de données, and untick Améliorer le modèle. Done correctly, model improvement is no longer selected.
If you use Grok through the X app, open account Paramètres, then Confidentialité et Sécurité, then Grok et collaborateurs tiers, and disable Autoriser l’utilisation de mes données publiques ainsi que de mes interactions, saisies et résultats obtenus avec Grok et xAI à des fins d’entraînement et d’ajustement. Done correctly, that permission is no longer enabled.
If you use DeepSeek, go to account Paramètres. On the web, open Profil. On mobile, open Contrôles des données. In both cases, turn off Améliorer le modèle pour tous. Done correctly, the setting is disabled in the relevant screen.
If you use Mistral Le Chat on the web, open Paramètres, then the Préférences tab in the Le Chat section, and untick Autoriser l’utilisation de vos interactions pour entraîner nos modèles. On mobile, open Contrôle des données et du compte and turn off Activer le partage de données. Done correctly, data sharing for training is off.
If you use LinkedIn, open your profile photo, then Préférences, then Confidentialité des données, then Données pour l’amélioration de l’IA générative, and turn off Utiliser mes données pour entraîner des modèles d’IA de création de contenu. Done correctly, that content training setting is off on your account.
If you use Meta AI on Meta services, use the rights centre and choose Comment m’opposer au traitement de mes informations. Then select either Je veux m’opposer à l’utilisation de mes informations par Meta AI or Je souhaite m’opposer à l’utilisation de mes informations par des tiers pour Meta AI, depending on your case. Done correctly, you submit the form that matches the data source you want to oppose.
If you use WhatsApp with Meta AI, use the dedicated form, choose Comment formuler une opposition au traitement de mes informations ?, then state that the request concerns l’IA par Meta. Done correctly, the request is sent through the Meta form route described by the CNIL.
After changing the setting, send yourself one clean test prompt with no personal details. Done correctly, you can use the service normally while knowing the training or activity option you changed remains off.
Finally, change your prompt habits. Do not paste health details, political views, union matters, or religious information unless the service clearly needs that information for the task. Done correctly, your future prompts contain less personal data even before any provider setting applies.

Illustrative example

Emma uses ChatGPT and Gemini at home. She asks for help with travel planning, complaint letters, and CV edits. One evening, she notices that her prompts often include her full name, phone number, and booking references.

She decides to fix this before the habit grows. First, she signs in to ChatGPT on the web. She opens account settings, then Gestion des données, then turns off Améliorer le modèle pour tous. She checks the page again and confirms the option is no longer enabled.

Next, she opens Gemini in her browser. She goes to the Activité tab and chooses Désactiver et supprimer l’activité for Activité dans les applications Gemini. She notices the CNIL warning that this may delete past conversations and disable future history. That is exactly what she wants, so she accepts the change.

Then she adjusts her own behaviour. She rewrites a complaint prompt without her address, order number, or phone number. Instead of pasting the full email thread, she pastes only the part needed to improve the tone and structure.

A week later, she uses both tools again. The settings remain off. Her new prompts are shorter, cleaner, and less personal. She still gets useful help, but she now shares less and keeps less history behind.

The near-miss

Now replay Emma's week with one step skipped. She turns off ChatGPT training, but she ignores Gemini activity because she assumes closing old tabs is enough. Later, she asks Gemini to rewrite a message about a medical appointment and includes names and timing details.

She then remembers that the CNIL says health information is sensitive data. She goes back to Gemini and only then sees the Activité dans les applications Gemini control and the option Désactiver et supprimer l’activité. She realises she left the service saving more than she intended. The concrete consequence is not drama or a headline. It is a preventable privacy leak into her own account history and a harder clean-up after the fact.

How to check it worked

The first check is visual. Reopen the exact menu where you changed the option. The toggle or checkbox should still be off. If you cannot find the setting again, you cannot be sure the change stuck.

The second check is functional. In Gemini, the CNIL says disabling activity can also disable conversation history and stop later conversations from being saved. If that was your goal, confirm that new chats no longer build the same visible history.

The third check is behavioural. Look at your last few prompts. If they still contain full names, phone numbers, booking codes, or health details, the setting change helped but your main risk remains your own copying and pasting.

The fourth check is scope. Some people use one provider in a browser, another in a mobile app, and a third inside a social platform. Verify each place separately. A setting changed in one service does not automatically protect a different service.

The fifth check is fallback. If the service offers a rights request form in addition to a settings toggle, keep that route in mind. The CNIL lists form-based options for Meta, WhatsApp, Gemini, and LinkedIn in some cases. If a setting seems unclear, the form route gives you another way to object.

Test yourself

Question: In ChatGPT, which menu named by the CNIL contains the setting to stop model improvement? Answer: The setting is in account settings under Gestion des données as Améliorer le modèle pour tous.

Question: What can happen in Gemini when you choose Désactiver et supprimer l’activité? Answer: The CNIL says it can delete past conversations and disable conversation history for future chats.

Question: Why is turning off a provider setting not enough on its own? Answer: Because you also need to stop pasting unnecessary personal or sensitive data into prompts.

Common mistakes

Assuming history and training are the same

They are related, but not identical. A model improvement option can be off while some chat records still exist. A history option can change future saving without automatically fixing all past use.

Changing one app and forgetting another

Many people use web and mobile versions interchangeably. The CNIL lists different paths for some providers, such as Gemini and DeepSeek. Check the version you really use.

Leaving old prompts full of identifiers

A privacy toggle helps from now on. It does not excuse bad prompt habits. Remove names, account numbers, and contact details unless they are truly needed for the task.

Pasting sensitive data into free-text boxes

The CNIL warns that users can type sensitive data into chatbots unexpectedly. Health details, political opinions, religion, and trade union information are poor candidates for casual prompts.

Thinking no account means no data trail

The CNIL explains that chatbots may still process personal data to keep a trace of the conversation, even without account creation or directly identifying details. Anonymous feeling is not the same as anonymous processing.

Waiting until after a problem

Some platforms require a form if you want to object more formally. That can mean choosing the right rights category and providing screenshots or examples. It is easier to reduce collection before your history grows.

Level up

Your next step is to apply the same check to every chatbot you use, not just your favourite one. The CNIL lists named controls for ChatGPT, Copilot, Claude, Gemini, Grok, DeepSeek, Mistral Le Chat, Meta AI, WhatsApp, and LinkedIn. Make one short pass through each account and turn off every model improvement or data sharing setting you can find.

Then add one personal rule: before you press send, remove anything you would not want sitting in a saved conversation. This matters most for sensitive data, which the CNIL treats with special care, and for everyday identifiers that quietly reveal more than you think.