Démarrage rapide
Ce guide couvre toutes les fonctionnalités de ChatGPT :
- Commencer — Create your OpenAI account and finish phone verification
- Comment utiliser la génération de texte — Draft emails, reports and social posts from one short prompt
- Comment utiliser l'analyse de données — Read raw data, run the maths and explain what it found
- Comment utiliser la navigation Web — Check the live internet before it answers
- Comment utiliser les modèles avancés — Switch between fast models and deep reasoning models
- How to Use Audio and Speech — Hold real voice conversations through the official app
- How to Use GPT Integrations — Run custom GPT bots trained on specialised subjects
- Comment utiliser la génération d'images par IA — Generate images with DALL-E 3 without leaving the conversation
- Comment utiliser Study and Learn — Explain hard topics simply and build practice material
- Comment utiliser les projets — Group work so ChatGPT remembers the brief every time
Temps nécessaire : 5 minutes par fonctionnalité
Vous trouverez également dans ce guide : Conseils de pro | Erreurs courantes | Dépannage | Tarification | Alternatives
Pourquoi faire confiance à ce guide ?
I have used ChatGPT daily since launch and tested every feature covered here. This tutorial comes from real hands-on work, not vendor screenshots.
ChatGPT is the Assistant IA that hundreds of millions of people now open before Google.
You can access ChatGPT free in any browser and get instant answers in seconds.
Most users stop at one box and one answer.
This guide shows you how to use ChatGPT properly, feature by feature.
Étape par étape, avec captures d'écran et conseils de pro.
Tutoriel ChatGPT
This complete How to Use ChatGPT tutorial walks through every feature in order.
It starts at your first prompt and ends with power-user habits.
ChatGPT
Write, research, analyse and create in one chat window. The free plan costs nothing. ChatGPT Plus adds GPT-4 class models, DALL-E 3 images and priority access for $20 a month. Download ChatGPT today and run your first prompt in under three minutes.
Premiers pas avec ChatGPT
Before any feature works, finish this one-time setup.
Cela prend environ trois minutes.
Here is what the process looks like in practice:
Passons maintenant en revue chaque étape.
Step 1: Create Your OpenAI Account
Go to the ChatGPT home page and click Sign up.
You can sign up with an email address, a Google login or a Microsoft account.
OpenAI asks for a valid phone number, and phone verification blocks throwaway signups.
✓ Point de contrôle: Vérifiez votre boîte de réception pour le message de confirmation.
Step 2: Open the Web App or Install the Mobile App
On desktop, click Log in and work straight from your browser.
On phones, install the official app rather than a mobile browser tab.
The mobile apps sync your chat history across devices and add voix conversations.
Voici à quoi ressemble le tableau de bord :
✓ Point de contrôle: You can see the message box and the side panel.
Step 3: Set Custom Instructions
Click your profile, then click Settings and open Custom Instructions.
Tell it your role, your industry and how long answers should be.
Every new chat now starts with that professional input already loaded.
✅ Terminé : Vous êtes prêt à utiliser n'importe quelle fonctionnalité ci-dessous.
Comment utiliser la génération de texte ChatGPT
Génération de texte lets you turn a rough idea into finished writing in seconds.
Voici comment l'utiliser étape par étape.
Étape 1 : Ouvrir une nouvelle conversation
Click New chat in the left side panel.
Type your first prompt into the message box and hit Enter.
Step 2: Add Context and an Output Contract
Prompt ChatGPT with your audience, format and length in one message.
Vague prompts create generic answers, so extra details sharpen every answer.
Voici à quoi cela ressemble :
✓ Point de contrôle: A finished draft appears below your request in the chat.
Étape 3 : Affiner le brouillon
Edit your initial prompt or ask for a rewrite.
✅ Résultat : You have publish-ready copy built from one prompt.
💡 Conseil de pro : Ask ChatGPT to act as a writing coach before you request the rewrite.
Comment utiliser l'analyse de données ChatGPT
Analyse des données lets you upload a spreadsheet and get charts without writing code.
Voici comment l'utiliser étape par étape.
Step 1: Attach Your File
Click the paperclip icon and pick a CSV or Excel file.
Advanced data analysis is included with ChatGPT Plus.
Step 2: Ask a Plain-English Question
Describe the answer you want, not the formula.
ChatGPT writes and runs Python code behind the scenes.
Voici à quoi cela ressemble :
✓ Point de contrôle: A chart or summary table renders inside the conversation.
Step 3: Download the Output
Request a chart or a cleaned file, then save it.
✅ Résultat : Hours of manual spreadsheet work finish in about two minutes.
💡 Conseil de pro : Ask for the code it ran so you can repeat the job next month.
How to Use ChatGPT Web Browser
Navigation Web lets you pull up-to-date information from live pages instead of stale memory.
Voici comment l'utiliser étape par étape.
Step 1: Ask a Time-Sensitive Question
Mention today, this week or 2026 in your request.
Web browsing switches on automatically for current topics.
Step 2: Check the Citations
Open the source links listed under the reply.
This is the fastest guard against misleading information.
Voici à quoi cela ressemble :
✓ Point de contrôle: Source links appear beneath the reply on the page.
Step 3: Narrow the Search
Name the exact site or report you trust most.
✅ Résultat : You get current facts with a citation trail you can verify.
💡 Conseil de pro : Paste a URL directly and ask for a summary of that single page.
Comment utiliser les modèles avancés de ChatGPT
Modèles avancés lets you pick a smarter engine for the jobs that actually need one.
Voici comment l'utiliser étape par étape.
Step 1: Open the Model Picker
Click the model name at the top of the page.
Plus subscribers get access to the GPT-4 model and later releases.
Step 2: Match the Model to the Task
Use reasoning models for maths, logic and long documents.
Fast models handle short chat and quick lookups better.
Voici à quoi cela ressemble :
✓ Point de contrôle: The model name at the top updates to your choice.
Step 3: Compare Two Answers
Re-run the same prompt on a second model.
✅ Résultat : Every request runs on the engine that suits it best.
💡 Conseil de pro : Priority access means paid users keep working during high traffic hours.
Comment utiliser ChatGPT Audio et Parole
Audio et parole lets you talk to ChatGPT out loud and listen to the reply.
Voici comment l'utiliser étape par étape.
Step 1: Install the Mobile App
Download the official app from the App Store or Google Play.
OpenAI offers mobile apps for iOS and Androïde.
Step 2: Tap the Headphone Icon
The headphone icon starts a hands-free voix session.
Speak normally and pause when you want the answer.
Voici à quoi cela ressemble :
✓ Point de contrôle: A pulsing cercle shows the app is listening to you.
Step 3: Keep the Thread Going
Ask follow-ups by voice without touching the screen.
✅ Résultat : You can work through ideas while walking or driving.
💡 Conseil de pro : Voice mode is the fastest way to capture creative inspiration on the move.
Comment utiliser les puissantes intégrations GPT de ChatGPT
Intégrations GPT puissantes lets you load a purpose-built assistant instead of re-explaining your job.
Voici comment l'utiliser étape par étape.
Étape 1 : Ouvrez la boutique GPT
Click Explore GPTs in the side panel.
ChatGPT Plus unlocks GPTs built on specialised data.
Step 2: Pick a Bot for Your Task
Search by job, then start a chat with it.
Each bot already carries its own instructions and files.
Voici à quoi cela ressemble :
✓ Point de contrôle: The bot name shows above the message box.
Step 3: Build Your Own
Click Create and describe the assistant you need.
✅ Résultat : A specialist AI assistant handles your repeat work.
💡 Conseil de pro : Save your best internal prompt as a private GPT for the whole team.
How to Use ChatGPT AI Image Generator
Génération d'images par IA lets you create artwork straight inside the chat window.
Voici comment l'utiliser étape par étape.
Step 1: Describe the Image
Write subject, style, mood and aspect ratio in one line.
DALL-E 3 reads long descriptions better than keyword lists.
Step 2: Request an Edit
Ask for a colour, angle or background change.
ChatGPT keeps the earlier version in context.
Voici à quoi cela ressemble :
✓ Point de contrôle: A generated picture appears inside the same chat.
Étape 3 : Enregistrer le fichier
Click the download arrow on the finished picture.
✅ Résultat : You have original artwork built from a plain-text request.
💡 Conseil de pro : Ask for three variations at once, then pick the strongest one.
How to Use ChatGPT Study and Learn Tool
Étudiez et apprenez lets you turn any subject into a study plan you will actually follow.
Voici comment l'utiliser étape par étape.
Step 1: Set Your Level
Say what you already know and where you struggle.
This is where tailored advice beats a generic textbook.
Étape 2 : Demander du matériel d’entraînement
Ask for practice quizzes, trivia or a study schedule.
Use Chain-of-Thought prompting so it explains each step of the reasoning.
Voici à quoi cela ressemble :
✓ Point de contrôle: A structured quiz or weekly schedule appears in the chat.
Step 3: Test Yourself
Answer without help, then ask for marking.
✅ Résultat : You hold a personal tutor that adapts to your gaps.
💡 Conseil de pro : Ask it to grade your answer harshly and provide feedback on weak spots.
Comment utiliser les projets personnalisés de ChatGPT
Projets personnalisés lets you keep related chats, files and rules in one folder.
Voici comment l'utiliser étape par étape.
Étape 1 : Créer un projet
Click Projects in the side panel, then name it.
Add the client, product or course it covers.
Step 2: Upload Reference Files
Drop style guides, briefs or data into the project.
Every chat inside it reads those files automatically.
Voici à quoi cela ressemble :
✓ Point de contrôle: New chats open inside the project with the files attached.
Step 3: Set Project Instructions
Write the tone and format rules once.
✅ Résultat : Your context loads itself instead of being re-typed daily.
💡 Conseil de pro : Custom Instructions save preferences for future chats across every project.
Conseils et raccourcis pour ChatGPT Pro
After years of daily use, these are the habits that save the most time.
Fine-tune your saved preferences every few months as your work changes.
Raccourcis clavier
| Action | Raccourci |
|---|---|
| Start a new chat | Ctrl + Maj + O |
| Focus the message box | Maj + Échap |
| Copy the last reply | Ctrl + Maj + C |
| Toggle the side panel | Ctrl + Maj + S |
Fonctionnalités cachées que la plupart des gens ignorent
- Archive instead of delete: Archive conversations to move less relevant chats out of the way without losing them.
- Share a chat by link: ChatGPT can generate a unique URL for one conversation, which beats pasting screenshots.
- Turn off training: In data controls you can stop new chats being used as training data for OpenAI’s models.
Here is the workspace I use for most of these habits:
Erreurs courantes à éviter dans ChatGPT
Mistake #1: Writing a One-Line Prompt
❌ Faux : Sending write a blog post and expecting a usable result.
✅ À droite : Name the reader, the format, the length and the tone in your first prompt.
Mistake #2: Trusting Every Answer
❌ Faux : Publishing figures straight from the chat without a check.
✅ À droite : Fact-check ChatGPT’s responses, because dates and figures can carry misleading information.
Mistake #3: Starting a New Chat for Every Question
❌ Faux : Opening a fresh thread after each reply and losing all context.
✅ À droite : Stay in one conversation, since ChatGPT remembers what you told ChatGPT earlier in that thread.
Dépannage de ChatGPT
Problem: Answers Are Generic or Wrong
Cause: Your prompt gave no audience, format or context.
Réparer: Rewrite the request with details, then ask it to explain its reasoning step by step.
Problem: The Page Is Slow or Unavailable
Cause: High traffic hits free accounts first during peak hours.
Réparer: Retry in a few minutes, or upgrade for general access even at busy times.
Problem: Your Chat History Disappeared
Cause: History is switched off in your data settings.
Réparer: Turn it back on, or you will not reach past conversations on any device.
📌 Note: If none of these fix your issue, contact OpenAI support.
Qu'est-ce que ChatGPT ?
ChatGPT est une IA chatbot from OpenAI that answers questions and creates content from plain-language prompts.
Think of it as a very fast research assistant who types.
It was trained on huge volumes of text, then tuned with reinforcement learning from human feedback.
That training is why it will reject inappropriate requests and refuse unsafe content or illegal activities.
It is not perfect. It can guess at incorrect premises and produce nonsensical answers.
Regardez ce bref aperçu :
Il comprend les fonctionnalités clés suivantes :
- Génération de texte : Drafts emails, reports and social posts from one short prompt.
- Analyse des données : Reads spreadsheets, runs the maths and returns charts.
- Navigation Web : Checks live sources for up-to-date information.
- Modèles avancés : Lets you switch engines for harder reasoning work.
- Audio and Speech: Runs voice conversations through the mobile app.
- Intégrations GPT : Loads custom bots built for one subject.
- Génération d'images par IA : Creates pictures with DALL-E 3 inside the chat.
- Étudier et apprendre : Builds quizzes, schedules and simple explanations.
- Projets: Keeps chats, files and rules grouped together.
Pour une analyse complète, consultez notre Avis sur ChatGPT.
Here is the interface you will be working in:
Tarification de ChatGPT
Here is what ChatGPT costs in 2026:
| Plan | Prix | Idéal pour |
|---|---|---|
| Gratuit | 0 $/mois | Casual users testing the basics |
| Plus | 20 $/mois | Daily users who want the newest model improvements |
| Pro | 200 $/mois | Researchers running heavy reasoning workloads |
| Équipe | 25 $/utilisateur/mois / 30 $/utilisateur/mois | Small teams sharing GPTs and workspaces |
Essai gratuit : No trial needed. The free plan is permanent, and you only pay when you want more.
Garantie de remboursement : None advertised. Cancel any time and the plan runs to the end of the billing period.
Here is the plan comparison inside your account:
💰 Meilleur rapport qualité-prix : Plus — OpenAI’s paid subscription costs $20 a month.
It adds GPT-4 class models, faster response times and priority access to new features.
ChatGPT contre les alternatives
How does ChatGPT compare against other chatbots? Here is how the leading AI chatbots line up:
| Outil | Idéal pour | Prix | Notation |
|---|---|---|---|
| ChatGPT | All-round daily work | 20 $/mois | ⭐ 4,7 |
| Claude | Long documents and writing | 20 $/mois | ⭐ 4,7 |
| Perplexité | Sourced research | 20 $/mois | ⭐ 4,5 |
| Grok | Real-time social context | 30 $/mois | ⭐ 4.2 |
| Recherche profonde | Low-cost reasoning | 0 $/mois | ⭐ 4,3 |
| Manus | Autonome agent tasks | 39 $/mois | ⭐ 4.1 |
| Andi Recherche | Ad-free search answers | 0 $/mois | ⭐ 4.0 |
| Vous.com | Multi-model search | 15 $/mois | ⭐ 4.2 |
Sélection rapide :
- Meilleur résultat global : ChatGPT — widest feature set and the largest GPT library.
- Meilleur budget : Deepseek — strong reasoning at no cost.
- Idéal pour les débutants : ChatGPT — the simplest first prompt experience of any AI chatbot.
- Best for cited research: Perplexity — every claim ships with a source link.
🎯 Alternatives à ChatGPT
Vous cherchez des alternatives à ChatGPT ? Voici les meilleures options :
- 🌟 Claude : Handles very long documents and keeps a warmer, more careful writing voice.
- 🔍 Perplexité: Search-first assistant that footnotes every claim with a live link.
- 🔥 Grok : Pulls real-time posts, so it reads breaking chatter faster than most.
- 💰 Recherche en profondeur : Open-weight models that give strong reasoning for free.
- 🚀 Manus : Agent-style tool that runs multi-step jobs while you do something else.
- 👶 Recherche Andi : Clean, ad-free answers for people who just want a quick result.
- 🎯 Vous.com : Lets you swap between several models inside one search page.
- 🧠 Gémeaux: Deep Google Workspace links for Docs, Gmail and Drive users.
- 💼 Copilote: Sits inside Microsoft 365, which suits Word and Excel heavy teams.
- ⚡ Pokee : Lightweight agent focused on quick automations and tool calls.
Pour la liste complète, consultez notre Alternatives à ChatGPT guide.
⚔️ Comparaison avec ChatGPT
Here is how ChatGPT stacks up against each competitor:
- ChatGPT contre Claude: Claude writes longer and cleaner. ChatGPT wins on images, data analysis and its GPT library.
- ChatGPT contre Perplexité: Perplexity is better for cited research. ChatGPT is better for creating the actual work.
- ChatGPT contre Grok : Grok is faster on live social news. ChatGPT is stronger at structured, careful output.
- ChatGPT contre Deepseek : Deepseek is cheaper. ChatGPT has the apps, voice mode and integrations around the model.
- ChatGPT contre Manus : Manus runs longer autonomous jobs. ChatGPT is more reliable for everyday desk work.
- ChatGPT contre Andi Search : Andi is a lighter search tool. ChatGPT does far more than answer questions.
- ChatGPT contre You.com : You.com offers model choice. ChatGPT offers depth inside one polished product.
- ChatGPT contre Gemini: Gemini wins for Google Workspace users. ChatGPT wins on custom bots and platform independence.
- ChatGPT contre Copilot : Copilot wins inside Office files. ChatGPT wins everywhere else, especially creative work.
- ChatGPT contre Pokee : Pokee targets automation. ChatGPT covers writing, analysis and images in one place.
Commencez à utiliser ChatGPT dès maintenant
Vous avez appris à utiliser toutes les principales fonctionnalités de ChatGPT :
- ✅ Génération de texte
- ✅ Analyse des données
- ✅ Navigation Web
- ✅ Modèles avancés
- ✅ Audio and Speech
- ✅ Intégrations GPT
- ✅ Génération d'images par IA
- ✅ Étudiez et apprenez
- ✅ Projets
Étape suivante : Choisissez une fonctionnalité et essayez-la dès maintenant.
La plupart des gens commencent par la génération de texte.
Cela prend moins de cinq minutes.
Foire aux questions
Puis-je utiliser ChatGPT gratuitement ?
Yes. The free plan covers basic chat and the mobile app at no cost. Paid plans add faster models and higher limits.
Combien coûte ChatGPT ?
Free is $0/month and Plus is $20/month. Pro costs $200/month. Team runs $25/user/month or $30/user/month depending on billing term.
Comment accéder à ChatGPT ?
Visit the ChatGPT home page, click Sign up, then use an email, Google or Microsoft account. A valid phone number completes phone verification.
Comment utiliser ChatGPT le plus efficacement possible ?
Give context, name your audience and set the output format in your first prompt. Then refine the reply instead of starting over.
Peut-on utiliser ChatGPT sans s'inscrire ?
Limited guest use exists on some pages. Without an account you cannot save chat history or reach past conversations.
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