Web & Development Tools

Formatting, converting and validating are part of everyday development. Our web tools handle these tasks quickly and reliably, with no backend and no code ever landing on a server.

The JSON Formatter makes nested data readable, while Base64 and Hash Generator encode and verify values. For CSS, HTML and SQL, minifiers, formatters and validators are available. Slug, timestamp, JWT and further converters cover many routine tasks.

Web & Development 38

URL Encoder / Decoder Encode or decode URLs and special characters for web addresses, so links transfer safely and process correctly in forms. Runs in your browser, GDPR-compliant. JSON Formatter Format, minify, and validate JSON data with syntax highlighting, keeping raw data readable or ready for efficient transfer. GDPR-compliant. Base64 Encoder / Decoder Encode text or decode Base64 data, for instance in email attachments and data URLs, whenever binary data must be transmitted as text. GDPR-compliant. Hash Generator Generate cryptographic hashes with MD5, SHA-1, SHA-256, and SHA-512 from your text to verify data integrity and file checksums. GDPR-compliant. UUID Generator Generate UUIDs version 4 for databases, APIs, and projects and copy them with one click, ready to use as unique identifiers. GDPR-compliant. Regex Tester Test regular expressions live in your browser with syntax highlighting and an instant match list, no installation required, right in the window. CPU Benchmark Measure browser compute performance with an integer workload and up to 64 threads to evaluate your hardware capabilities. Runs in your browser, GDPR-compliant. Markdown to HTML Convert Markdown to clean HTML with live preview and formatting like lists and code blocks, ideal for websites and documentation. GDPR-compliant. JSON to CSV Converter Convert JSON data to CSV and back, ideal for spreadsheets and Excel, so you can edit data flexibly and in a structured way. GDPR-compliant. JSON to YAML Converter Convert between JSON and YAML, handy for configuration files like Docker Compose, so you can quickly adjust your settings. Runs in your browser, GDPR-compliant. XML to JSON Converter Convert XML to JSON and back, fast for APIs and config files, so you can use data structures flexibly for different applications. GDPR-compliant. HTML Entities Encoder/Decoder Encode special characters as HTML entities or decode them to readable text, ensuring your pages display correctly across browsers. GDPR-compliant. HTML Minifier Minify HTML code for faster load times without touching any scripts, so your web pages stay lean and deliver content more quickly. GDPR-compliant. Slug Generator Create URL-friendly slugs from any title or text, including umlauts, and use them directly in your links and navigation. Runs in your browser, GDPR-compliant. Timestamp Converter Convert Unix timestamps to readable dates and back, automatically detected, and find the exact time behind every single event. GDPR-compliant. Display Size Calculator Calculate width and height from screen diagonal in inches and centimeters, to find the right monitor size for your desk setup. GDPR-compliant. PX to REM Converter Convert pixels to REM and EM and back, with selectable base font size, to keep your typography scalable across devices and screens. GDPR-compliant. Media Query Generator Generate CSS media queries for responsive designs, via preset or manually, and adapt your layout to fit every screen size. Runs in your browser, GDPR-compliant. Responsive Viewport Tool Find out which device class your content width falls into, with common breakpoints, to optimize your layout with targeted adjustments. GDPR-compliant. CSS Minifier Minify CSS code for faster load times, without breaking strings and url() values, and keep full control of your stylesheets. GDPR-compliant. CSS Formatter Format messy CSS code into clean, readable indented structure, and bring clear order to your stylesheets with one click. Runs in your browser, GDPR-compliant. jQuery to Vanilla JS Convert common jQuery methods to modern vanilla JavaScript, to gradually move your projects off the old library with confidence. GDPR-compliant. SQL Formatter Format SQL neatly with indentation and highlighted keywords, making your code easier to read, review, and maintain over time. GDPR-compliant. JWT Decoder & Inspector Decode and inspect JSON Web Tokens, your token stays local in your browser, and check claims and headers securely at a glance. CSS Validator Check CSS for errors such as missing colons and unknown properties, with precise line numbers pointing to each issue. Runs in your browser, GDPR-compliant. HTML Source Cleaner Clean HTML source by removing classes, scripts and styles while keeping the semantic markup intact, entirely in your browser. HTML to Markdown Convert your HTML source code into readable Markdown while reliably preserving headings, lists, tables and code blocks. Runs in your browser, GDPR-compliant. HTML Pretty Printer Format HTML cleanly with 2-space indentation, keeping pre, script and style elements untouched in their original form. Runs in your browser, GDPR-compliant. JS Minifier Minify your JavaScript code by stripping comments and unnecessary whitespace safely, without changing the semantics. Runs in your browser, GDPR-compliant. CSS Selector Generator Generate a unique CSS selector for any element from pasted HTML, with a live preview, highlighting and one-click copy. Runs in your browser, GDPR-compliant. File Size Converter Convert file sizes between B, KB, MB, GB, TB and PB for a quick size comparison, classification and easy reference. Runs in your browser, GDPR-compliant. Website Auditor Audit any public URL for SEO factors like HTTP status, title, meta description, H1, alt text, canonical, and sitemap.xml, with pass/fail score. Keyboard Tester Check whether every key on your keyboard registers correctly. Choose your layout (German QWERTZ, English US or UK), start typing, and watch each physical key light up with its key code and modifiers. Fully local. Refresh Rate Test Measures the real refresh rate of your display in Hertz. The test runs for five seconds via requestAnimationFrame and shows the average, minimum, and maximum. Entirely local. Gamepad Tester Check whether your controller is detected and watch every button and analog stick respond live (Gamepad API). Connect the gamepad, press start, and test. Fully local. Cron Generator Visually builds a 5-field cron expression and outputs a human description of when the job runs. Includes presets and validation. Meta Tags Generator Generates ready-to-copy HTML meta tags for SEO: title, description, Open Graph, canonical, robots and more. Robots.txt Generator Builds a robots.txt from rules: user-agent, allow, disallow and sitemap. Ready to copy into your webroot.