miniDevToolkit is a free collection of browser-based developer tools. Every tool runs entirely in your browser. Your data never leaves your device. No sign-up is required.
The JSON Toolkit gives you seven tools in one place. Use the Formatter to beautify JSON with adjustable indentation. Use the Validator to check if your JSON is valid. Convert JSON to CSV, XML, or YAML with a single click. Minify JSON to reduce its size. Compare two JSON objects side by side with the Diff tool. Everything runs in your browser instantly.
The Encoding Toolkit handles 14 common encoding tasks. Encode and decode Base64 text and images. Encode and decode URLs and HTML entities. Decode JWT tokens to see their header, payload, and expiry. Convert text to Hex or Unicode escape sequences. Encode and decode Morse code. All encoding runs locally with no server involved.
The Generators toolkit creates common developer assets. Generate UUID v4, v1, or nil format — up to 100 at once. Create secure random passwords with a strength meter. Generate Lorem Ipsum placeholder text by word, sentence, or paragraph. Create QR codes with custom colors and download them as PNG files.
The Fake Data Generator creates realistic test data for forms, APIs, and databases. Choose from 40 built-in fields including names, emails, phone numbers, addresses, company names, UUIDs, and credit card numbers. Add custom fields with static text, random numbers, or date ranges. Generate up to 1,000 rows and export as JSON or CSV.
The Hash and Security toolkit computes MD5, SHA-256, and SHA-512 hashes for text and files. Type or paste any text to see all three hashes at once. Drag and drop a file to compute its hash locally without uploading anything. The tool uses the Web Crypto API built into your browser.
The File Converter handles four common conversion tasks. Convert PDF to PNG images. Convert PDF to a Word document. Convert a Word document to PDF. Combine multiple JPG or PNG images into a single PDF. All conversions run in your browser using JavaScript libraries. No files are ever uploaded to a server.
The Time and Date toolkit covers three common developer tasks. The Unix Timestamp Converter turns any timestamp into a readable date with full breakdown. The Timezone Converter shows a single time across 35 world timezones at once. The Cron Expression Builder lets you create cron schedules visually and shows the next five run times in plain English.
The Text Utilities toolkit helps you work with text. The Diff tool highlights exactly which lines changed between two texts. The Case Converter outputs your text in 12 formats at once including camelCase, snake_case, and kebab-case. The Regex Tester highlights matches in real time and includes 10 built-in presets for common patterns like email addresses and URLs.
The Compression Toolkit reduces file sizes without uploads. Compress JPG, PNG, and WebP images with a quality slider. Compress PDFs in the browser. Bundle multiple files into a ZIP archive. Optimize SVG files. Minify CSS, HTML, and JSON to remove whitespace and reduce file size. All compression runs client-side with no data sent to any server.
The Compression Toolkit reduces file sizes entirely in your browser. Compress JPG, PNG, and WebP images using a quality slider and optional maximum file size target. Compress PDF files using pdf-lib. Bundle multiple files into a ZIP archive using fflate. Optimize SVG markup to remove redundant attributes. Minify CSS, HTML, and JSON by stripping whitespace and comments. No files are uploaded to any server.
Every tool on miniDevToolkit runs entirely in your browser using JavaScript, the Web Crypto API, and the Canvas API. When you hash a file, compress an image, decode a JWT, or generate fake data, no network request is made containing your content. You can verify this by opening your browser DevTools, going to the Network tab, and using any tool — zero outbound data requests will appear. The only external requests are for loading the page itself, Google Fonts, and optional CDN libraries like PDF.js.
Is miniDevToolkit free? Yes. All tools are free to use with no account and no sign-up required. There are no premium tiers or paywalls.
Is my data private? Yes. Every tool runs entirely in your browser. Your JSON, files, passwords, hashes, and text are never sent to any server.
Does it work offline? Yes. Once the page loads, all core tools work without an internet connection. Tools that use CDN libraries (PDF.js, jsPDF) require the CDN to load once on first use.
Who built miniDevToolkit? miniDevToolkit was built by Aqib Javed, a software developer. Visit aqibjaved.vercel.app to learn more.
How many tools does miniDevToolkit have? miniDevToolkit currently offers 25+ tools across 9 toolkits: JSON Toolkit, Encoding Toolkit, Generators, Fake Data Generator, Hash and Security, File Converter, Time and Date Tools, Text Utilities, and Compression Toolkit.