Fast, private, no-signup tools for developers, designers, and writers. Everything runs in your browser — your data never leaves your device.
Format, validate, and minify JSON data with syntax highlighting.
Encode text to Base64 or decode Base64 back to plain text.
Generate QR codes for URLs, text, WiFi, or contact info. Download as PNG.
Count words, characters, sentences, and estimate reading time.
Generate random UUIDs (v4) in bulk. Copy with one click.
Convert between HEX, RGB, and HSL color formats instantly.
Test and debug regular expressions with real-time match highlighting.
Encode special characters for URLs or decode percent-encoded strings.
Convert Unix timestamps to dates and vice versa. Seconds & milliseconds.
Generate MD5, SHA-1, SHA-256, SHA-512 hashes for any text instantly.
Write Markdown and see rendered HTML in real-time. Copy HTML output.
Generate placeholder text for designs. Paragraphs, sentences, or words.
Compress CSS to reduce file size or beautify minified CSS for readability.
Decode JSON Web Tokens to inspect header, payload, and expiration.
DevToolBox is a collection of free, browser-based developer tools designed with one goal in mind: making your daily workflow faster and more efficient. Whether you are a software engineer debugging API responses, a designer picking the perfect color palette, or a writer checking word counts for a blog post, DevToolBox has a tool that can help.
Every tool on this site runs entirely in your browser. Your data never leaves your device, and nothing is stored on any server. There are no accounts to create, no software to install, and no hidden costs. Just open the tool you need, get your work done, and move on.
Unlike many online tools that upload your data to remote servers for processing, DevToolBox performs all operations using JavaScript running directly in your browser. When you format JSON, generate a hash, or decode a JWT, the computation happens on your machine. This means sensitive data like API tokens, configuration files, or proprietary code never touches a third-party server. For developers working with confidential data or in regulated industries, this is not just a convenience — it is a requirement.
DevToolBox is built with vanilla HTML, CSS, and JavaScript — no heavy frameworks, no build steps, no unnecessary dependencies. Pages load in under a second on most connections. Each tool is a self-contained page that does one thing well, following the Unix philosophy of small, focused utilities that compose together to solve larger problems.
The tools in DevToolBox cover a wide range of common development tasks. During the planning phase, you might use the Lorem Ipsum Generator to create placeholder text for mockups, or the Color Converter to translate design specs between HEX, RGB, and HSL formats. While building features, the JSON Formatter helps you debug API responses, the Regex Tester validates your pattern matching logic, and the Base64 encoder handles data transformation. For deployment and security, the Hash Generator creates checksums for file integrity, the CSS Minifier reduces your stylesheet size, and the JWT Decoder helps you inspect authentication tokens.
Developers often waste time switching between different websites, installing desktop applications, or writing quick throwaway scripts to handle routine tasks. DevToolBox consolidates 14 of the most commonly needed utilities into a single, fast-loading site. Bookmark it once, and you have instant access to formatting, encoding, generating, validating, and converting tools whenever you need them. No context-switching, no distractions.
Each tool includes detailed documentation explaining the underlying technology, step-by-step usage guides, real-world examples, and answers to frequently asked questions. Whether you are a seasoned developer who needs a quick reference or a student learning about concepts like cryptographic hashing or regular expressions for the first time, you will find practical, accurate information alongside each tool.
DevToolBox is and will always be free to use. There are no premium tiers, no feature gates, and no usage limits. The site is supported by non-intrusive advertising, which allows us to keep the tools available to everyone without compromising on quality or privacy. We believe that basic developer utilities should be accessible to all — from independent freelancers to large engineering teams — regardless of budget.
Have a suggestion for a new tool or found a bug? We would love to hear from you. Visit our Contact page to get in touch, or learn more about the project on our About page.