Tous les guides
50 guides pour tirer le meilleur des outils en ligne gratuits — tutoriels pas à pas, explications approfondies, comparaisons et conseils.
How to Encode and Decode Base64 — Guide complet
Learn what Base64 encoding is, how it works, when to use it, and how to encode and decode Base64 in your browser —no tools or signup needed.
comparisonBase64 vs Codage Hex : Lequel devriez-vous utiliser ?
Compare Base64 and Hex encoding across efficiency, readability, use cases, and trade-offs — and learn when to pick each for binary-to-text encoding.
explanationFormats de couleur expliqués : HEX, RGB et HSL
Understand the three most common web color formats —HEX, RGB, and HSL —how each represents color, when to use which, and how to convert between them.
comparisonCSV vs TSV : Quel format de délimiteur utiliser ?
Compare CSV and TSV across delimiter choice, escaping, compatibility, and use cases — and learn when to pick each for tabular data.
referenceEnregistrements DNS expliqués : A, AAAA, MX, TXT, CNAME, NS
A complete reference guide to DNS record types —A, AAAA, MX, TXT, CNAME, and NS —with examples, use cases, and how to look them up.
explanationAlgorithmes de hachage expliqués : MD5, SHA-1, SHA-256, SHA-512
Understand cryptographic hash functions: differences between MD5, SHA-1, SHA-256, and SHA-512, and which to use for integrity checks vs password storage.
how-toComment Compress Images Without Losing Quality
Step-by-step guide to compressing images (JPEG, PNG, WebP) to reduce file size without visible quality loss using a free browser-based tool.
how-toComment Compress PDF Files Step by Step
Step-by-step guide to compressing PDF files to reduce file size using a free browser-based tool. Learn compression levels and what affects PDF size.
how-toComment Convert Colors Between HEX, RGB, and HSL
Step-by-step guide to converting colors between HEX, RGB, HSL, and other formats using a free browser-based tool. Learn when to use each format.
how-toComment Convert CSV to JSON Step by Step
Step-by-step guide to converting CSV data to JSON using a free browser-based tool. Learn header handling, nested structures, and common pitfalls.
how-toComment Convert Markdown to HTML Step by Step
Step-by-step guide to converting Markdown text to HTML using a free browser-based tool. Learn syntax, extensions, and common use cases.
how-toComment Convert Text to Binary and Back Step by Step
Step-by-step guide to converting text to binary (0s and 1s) and decoding binary back to text using a free browser-based tool. Learn ASCII and UTF-8.
how-toComment Convert Unix Timestamps to Human-Readable Dates (Step-by-Step)
Step-by-step guide to converting Unix timestamps (epoch) to human-readable dates and back using a free browser-based tool. Learn seconds vs milliseconds.
how-toComment Decode JWT Tokens and Inspect Claims Safely
Step-by-step guide to decoding JWT (JSON Web Token) tokens and inspecting their header and payload claims using a free browser-based tool. Learn security boundaries.
how-toComment Encode and Decode Base64 Strings Step by Step
Step-by-step guide to encoding text to Base64 and decoding Base64 back to text using a free browser-based tool. No upload, no signup, fully private.
how-toComment Encode and Decode URLs Step by Step
Step-by-step guide to URL encoding (percent-encoding) and decoding using a free browser-based tool. Learn why and when to encode URLs.
how-toComment Extract Text from PDF Files Step by Step
Step-by-step guide to extracting text content from a PDF file using a free browser-based tool. Learn scanned vs digital PDFs.
how-toComment Format and Validate JSON Data Step by Step
Step-by-step guide to formatting (beautifying) and validating JSON data using a free browser-based tool. Catch syntax errors, minify, and pretty-print JSON instantly.
how-toComment Generate Hash Values Step by Step
Step-by-step guide to generating cryptographic hash values (SHA-256, SHA-1, MD5) using a free browser-based tool. Learn use cases and security tradeoffs.
how-toComment Generate Secure Passwords Step by Step
Step-by-step guide to generating strong, random passwords using a free browser-based tool. Learn password length, character sets, and security best practices.
how-toComment Generate UUIDs Step by Step
Step-by-step guide to generating UUIDs (Universally Unique Identifiers) using a free browser-based tool. Learn UUID v4, v1, and when to use each.
how-toComment Merge PDF Files Step by Step
Step-by-step guide to merging (combining) multiple PDF files into one using a free browser-based tool. Learn ordering and page ranges.
how-toComment Resize Images Step by Step
Step-by-step guide to resizing images (change width and height) using a free browser-based tool. Learn aspect ratio, upscaling, and common dimensions.
how-toComment Split PDF Files Step by Step
Step-by-step guide to splitting a PDF file into multiple parts or extracting specific pages using a free browser-based tool.
how-toComment Test Regular Expressions Step by Step
Step-by-step guide to testing and debugging regular expressions using a free browser-based tool. Learn flags, capture groups, and common patterns.
how-toComment Use a Color Picker to Find Colors from Any Pixel
Step-by-step guide to using a color picker to find the exact color (HEX, RGB, HSL) of any pixel in an image or on screen using a free browser-based tool.
explanationBonnes pratiques de formatage JSON : lisible, valide et efficace
Understand the conventions for formatting JSON: indentation, key ordering, minification, trailing commas, and when to pretty-print vs minify.
explanationComprendre JSON : Un guide pour débutants sur le formatage et la validation
Apprenez ce qu'est JSON, ses règles de syntaxe, les types de données courants et comment formater et valider des données JSON avec des outils en ligne gratuits.
comparisonJSON vs XML : Quel format de données utiliser ?
Compare JSON and XML across syntax, verbosity, parsing speed, ecosystem support, and use cases — and learn when to pick each.
comparisonJSON vs YAML : Quel format de configuration utiliser ?
Compare JSON and YAML across readability, features, use cases, and trade-offs — and learn when to pick each for configuration and data interchange.
how-toComment Decode a JWT and Inspect Its Claims Safely
Learn the three-part structure of a JSON Web Token, how to decode the header and payload without verifying, and why decoding is not the same as trusting.
comparisonMarkdown vs HTML : Lequel utiliser pour le contenu ?
Compare Markdown and HTML across readability, expressiveness, learning curve, use cases, and rendering —and learn when to pick each (or both).
problem-solvingSécurité des mots de passe : Comment générer, stocker et auditer des mots de passe forts
Solve the most common password security problems: generating strong passwords, hashing them correctly, avoiding reuse, and auditing existing credentials.
comparisonCompresseur PDF vs Compresseur d'images : Duquel avez-vous besoin ?
Compare PDF and Image compression across targets, techniques, quality trade-offs, and use cases — and learn which tool to use for your file size problem.
referenceAide-mémoire des expressions régulières : syntaxe, indicateurs et motifs courants
Complete regex reference: metacharacters, character classes, quantifiers, anchors, groups, flags, and ready-to-use patterns for emails, URLs, and dates.
how-toComment Convert Unix Timestamps to Human-Readable Dates
Learn what a Unix timestamp is, how to convert it to a human-readable date and back, and how to handle time zones correctly when working with epoch time.
referenceRéférence de conversion d'unités : longueur, masse, température et aire
A complete reference of conversion factors for length, mass/weight, temperature, and area, with exact formulas and worked examples for each.
how-toHow to Encode and Decode URLs — Guide complet
Learn what URL encoding (percent-encoding) is, why it is required, and how to encode and decode URLs in your browser —no signup, fully private.
comparisonUUID v1 vs v4 vs v5 : Quelle version utiliser ?
Compare UUID versions 1, 4, and 5: how each is generated, their trade-offs in uniqueness, ordering, and determinism, and which to pick for your use case.
explanationQu'est-ce que le codage Base64 ? Une explication complète
A clear explanation of what Base64 encoding is, how it works, its character set, and why it is not encryption.
explanationQu'est-ce que CSV ? Une explication complète des valeurs séparées par des virgules
A clear explanation of what CSV (Comma-Separated Values) is, its syntax rules, common variations, and when to use CSV vs JSON.
explanationQu'est-ce que le hachage ? Une explication complète des fonctions de hachage
A clear explanation of what hashing is, properties of cryptographic hash functions, common algorithms (SHA-256, MD5), and use cases.
explanationQu'est-ce que JSON ? Une explication complète de JavaScript Object Notation
A clear explanation of what JSON (JavaScript Object Notation) is, its syntax, data types, history, and why it replaced XML as the web's data format.
explanationQu'est-ce qu'un JWT ? Une explication complète des JSON Web Tokens
A clear explanation of what a JWT (JSON Web Token) is, its three-part structure, how it is used for authentication, and security considerations.
explanationQu'est-ce que Markdown ? Une explication complète du langage de balisage léger
A clear explanation of what Markdown is, its syntax, why it is popular for documentation, and how it converts to HTML.
explanationQu'est-ce qu'une expression régulière ? Une explication complète
A clear explanation of what a regular expression (regex) is, its syntax, common use cases, and why regex is powerful but hard to read.
explanationQu'est-ce qu'un horodatage Unix ? Une explication complète du temps epoch
A clear explanation of what a Unix timestamp is, the Unix epoch, seconds vs milliseconds, and the Year 2038 problem.
explanationQu'est-ce que le codage URL ? Une explication complète du codage percent
A clear explanation of what URL encoding (percent-encoding) is, which characters need encoding, and how it works.
explanationQu'est-ce qu'un UUID ? Une explication complète des identifiants uniques universels
A clear explanation of what a UUID is, its versions (v1, v4, v5), structure, collision probability, and when to use UUIDs.
how-toComment Count Words, Characters, and Reading Time Accurately
Learn how word and character counts are defined across languages, how to estimate reading time, and how to use a counter to hit limits for essays, tweets, and meta descriptions.