Developer Guides & Tutorials

Free online WebP to JPG/PNG converter that runs entirely in your browser. Fixes the classic "my WhatsApp photo saved as .webp and won't open" problem - upload the .webp file and get a JPG or PNG instantly. Nothing is ever uploaded to a server. Available in English and Español.

Free online OGG (Opus) to MP4 converter that runs entirely in your browser via WebAssembly (ffmpeg.wasm). Pick a bitrate, and download an MP4 audio file that plays everywhere. Nothing is ever uploaded to a server. Available in English and Español.

Free online QR code generator that runs entirely in your browser with plain JavaScript - the full Reed-Solomon error-correction algorithm, no external library, no upload. Type any text or URL, pick a size, and download a ready-to-use PNG. Available in English and Español.

Free online image cropper that runs entirely in your browser. Move and resize the crop frame by hand with full freedom, optionally lock an aspect ratio, and download the result as PNG, JPEG or WebP. Nothing is ever uploaded to a server. Available in English and Español.

Free online WebM to MP4 converter that runs entirely in your browser via WebAssembly (ffmpeg.wasm). Pick a quality preset, optionally cap the resolution, and download an MP4 that plays everywhere. Nothing is ever uploaded to a server. Available in English and Español.

Free online cron expression parser. Paste a 5-field cron expression to get a plain-English description and see the next run dates, computed instantly in your browser. Supports steps, ranges, lists and the @daily/@hourly shorthands. Available in English and Español.

Free online Unix timestamp converter. Convert epoch time (seconds or milliseconds) to a human-readable date and back, in any timezone, plus a live-updating current timestamp and ISO 8601/RFC formats. Runs entirely in your browser. Available in English and Español.

Free online color converter. Pick a color or type a HEX code to instantly get its RGB, HSL, HSB/HSV and CMYK values, plus ready-to-use CSS, ten shades/tints and one-click copy. Runs entirely in your browser. Available in English and Español.

Free online image compressor and converter. Shrink JPG, PNG and WebP files with a quality slider and optional resizing, convert between formats, and see the real before/after size before downloading. Nothing is ever uploaded. Available in English and Español.

Free online PDF compressor that runs entirely in your browser. It rasterizes every page to guarantee a smaller file no matter what it contains, pick a compression level, and see the real before/after size before downloading. Nothing is ever uploaded. Available in English and Español.

Free online tool that converts JSON into TypeScript interfaces and Zod validation schemas. Infers optional fields, nested types, arrays and string literal unions (enums) directly from your data, all in your browser. No sign-up, nothing is uploaded. Available in English and Español.

Free online SVG logo generator. Type your name or initials, pick a font, colors and a background shape (circle, square, rounded square or hexagon) and get a crisp, scalable logo you can preview live and download as SVG or PNG. No sign-up, nothing is uploaded. Available in English and Español.

Free online README.md generator and live previewer. Write Markdown in a wide, distraction-free editor with formatting shortcuts and ready-made sections (badges, installation, usage, license) and see exactly how it will render on GitHub. Available in English and Español.

Free online hash generator. Type or paste text to get its MD5, SHA-1, SHA-256, SHA-384 and SHA-512 hash instantly, computed entirely in your browser. No sign-up, nothing is uploaded. Available in English and Español.

Free online XML formatter and validator. Paste your XML to beautify it with indentation, minify (compress) it, or validate that it is well-formed, instantly, right in your browser. Available in English and Español.

Convert an image to Base64 (data URI) or a Base64 string back into an image, free and online. Everything runs in your browser - your image is never uploaded to a server and is not saved anywhere. Available in English and Español.

Free online UUID generator. Instantly generate random UUID v4 or time-ordered UUID v7 identifiers in bulk, with options for uppercase letters and no hyphens. Runs entirely in your browser. Available in English and Español.

Free online diff checker. Compare two blocks of text or code line by line, with clear highlighting of additions and deletions plus an added/removed line count. Options to ignore case and whitespace. Runs entirely in your browser. Available in English and Español.

Free online JWT decoder. Paste a JSON Web Token to instantly see its decoded header and payload, with human-readable expiration dates and a clear warning that the signature is never verified. Runs entirely in your browser. Available in English and Español.

Free online regex tester. Test JavaScript regular expressions against sample text with live match highlighting, capture groups, all standard flags (g, i, m, s, u, y) and a replace mode. Runs entirely in your browser. Available in English and Español.

Free online Base64 encoder and decoder. Convert text or strings to Base64 and back instantly in your browser, with an optional URL-safe mode (RFC 4648). No sign-up, nothing is uploaded. Available in English and Español.

Free online tool to format, validate and minify JSON. Paste your JSON, get instant syntax error detection with line and column, a clean indented view, and one-click copy or download. Available in English and Español.

Beautiful template to manage your employees. A top-notch premium template for your next web project and employee management.

Facebook Login It is a very interesting tool that allows to speed up the login in websites and applications. Thus, when we enter with our Facebook user, the application or website takes the data we have associated with the profile, such as: name, surname, age range, sex and email. The above turns out to be more agile and comfortable for the user as beneficial for the system administrator.

A downloadable Angular 6 example covering a full CRUD flow: login with HTTP client integration, a paginated user list from an API, user detail, delete confirmation, and a validated add-user form.

This repository will show you how to implement the data model in an application with Ionic 3 and show you how to pass data from one class to another class using an interface.

Aquí en este tutorial, le hacemos aprender cómo crear un formulario de registro simple con la validación adecuada usando jQuery. Hemos creado un formulario HTML con CSS simple con cuatro campos: Nombre, Correo electrónico, Usuario. Y contraseña. Hay una función jQuery para la validación completa y los datos del usuario se insertan a través del script

Learn how to develop a fully functional shopping cart using core PHP and MySQL, without frameworks. This tutorial is beginner-friendly and teaches you how to handle session storage, display product listings from a database, and add interactivity with JavaScript. It´s a great starting point for anyone looking to understand the mechanics behind eCommerce systems and apply them in their own projects.

Browse the full Font Awesome 4 icon set in a searchable cheat sheet. Click any icon to copy its HTML tag, unicode entity, or CSS rule, ready to paste into your own project.

Git is a system for version control designed to handle projects quickly and efficiently. Programmers around the world must work with many files of different sizes and complexities to build their software projects, so it is necessary to manage all those lines of code with a system that allows to do it in a simple and safe way. Git stores the data in a small file system which mainly has three phases to make the changes in the projects: preparation, modification and confirmation.

When using AJAx in the right direction, it will greatly improve the user experience. In this article, let´s see how to upload images using jQuery through AJAX and add a great experience. Showing preview without page refresh, showing the progress bar, adding preview with fade in effect, small additions of features to the upload of your image will help the user.