Developer Resources 2026 — Complete Toolkit for Web Developers

Web developers waste significant time:

•Hunting for a reliable JSON formatter that handles large payloads •Finding a Base64 encoder that doesn't upload your credentials to a server •Locating a JWT decoder that works offline without an account •Testing regex patterns across multiple tools because none shows match groups clearly

ToolMasterApp consolidates 130+ developer and productivity tools in one place. All browser-based, all free, all private — your code and credentials never leave your device.

<a href="https://toolmasterapp.in/json-formatter" class="text-primary font-medium hover:underline" rel="noopener noreferrer">JSON Formatter</a> — Format, validate, and minify JSON with syntax highlighting. Tree view for exploring deeply nested structures. Handles multi-MB API responses without freezing.

Key features: •Real-time validation with exact error location •Collapsible tree view for complex nested objects •One-click minification for production •Dark mode with colour-coded syntax

Use case: Paste a raw API response → instantly see the structure and find the field you need.

<a href="https://toolmasterapp.in/base64" class="text-primary font-medium hover:underline" rel="noopener noreferrer">Base64 Encoder/Decoder</a> — Encode text, files, or images to Base64 and decode Base64 strings back to original content. Essential for:

•Authorization headers: <code class="px-1.5 py-0.5 rounded bg-muted text-foreground text-sm font-mono">Authorization: Basic base64(user:pass)</code> •Embedding images in CSS/HTML as data URIs •Decoding Base64-encoded API responses •Encoding binary file content for JSON payloads

<a href="https://toolmasterapp.in/url-encoder" class="text-primary font-medium hover:underline" rel="noopener noreferrer">URL Encoder/Decoder</a> — Encode special characters for URLs and query strings. Decode percent-encoded URLs to human-readable format.

<a href="https://toolmasterapp.in/html-encoder" class="text-primary font-medium hover:underline" rel="noopener noreferrer">HTML Entity Encoder</a> — Convert special characters to HTML entities for safe display in browsers.

<a href="https://toolmasterapp.in/jwt-decoder" class="text-primary font-medium hover:underline" rel="noopener noreferrer">JWT Decoder</a> — Paste any JSON Web Token to see: •Header (algorithm, token type) •Payload (claims, expiration, user ID) •Signature verification status

Critical: Use a browser-based decoder. Pasting JWTs into external websites risks token theft. ToolMasterApp decodes locally — your tokens never leave your browser.

<a href="https://toolmasterapp.in/password-generator" class="text-primary font-medium hover:underline" rel="noopener noreferrer">Password Generator</a> — Generate cryptographically secure passwords with configurable length and character sets. Runs locally with the Web Crypto API — no network calls.

<a href="https://toolmasterapp.in/hash-generator" class="text-primary font-medium hover:underline" rel="noopener noreferrer">Hash Generator</a> — Generate MD5, SHA-1, SHA-256, and SHA-512 hashes for text strings. Useful for verifying file integrity and debugging hash-based authentication.

<a href="https://toolmasterapp.in/regex-tester" class="text-primary font-medium hover:underline" rel="noopener noreferrer">Regex Tester</a> — Test regular expressions with: •Real-time match highlighting •Named group extraction •Global, multiline, and case-insensitive flag toggles •Common regex pattern library (email, URL, phone, date)

<a href="https://toolmasterapp.in/api-tester" class="text-primary font-medium hover:underline" rel="noopener noreferrer">API Tester</a> — Send HTTP requests (GET, POST, PUT, DELETE) directly from your browser. Set custom headers, request body, and authentication. View response status, headers, and formatted body.

<a href="https://toolmasterapp.in/cors-tester" class="text-primary font-medium hover:underline" rel="noopener noreferrer">CORS Tester</a> — Check CORS headers on any URL. Diagnose cross-origin request failures without writing code.

<a href="https://toolmasterapp.in/gradient-generator" class="text-primary font-medium hover:underline" rel="noopener noreferrer">CSS Gradient Generator</a> — Create linear and radial gradients with a visual editor. Copies the CSS code instantly.

<a href="https://toolmasterapp.in/color-picker" class="text-primary font-medium hover:underline" rel="noopener noreferrer">Color Picker</a> — Pick colors visually, convert between HEX, RGB, HSL, and CMYK. Generate color palettes from any base color.

<a href="https://toolmasterapp.in/box-shadow-generator" class="text-primary font-medium hover:underline" rel="noopener noreferrer">Box Shadow Generator</a> — Create CSS box shadows with live preview. Adjust blur, spread, offset, and color interactively.

<a href="https://toolmasterapp.in/flexbox-tester" class="text-primary font-medium hover:underline" rel="noopener noreferrer">Flexbox Playground</a> — Test flexbox properties visually. Select justify-content, align-items, and flex-direction and see the result instantly.

<a href="https://toolmasterapp.in/code-minifier" class="text-primary font-medium hover:underline" rel="noopener noreferrer">Code Minifier</a> — Minify CSS and JavaScript files. Reduces file size by 30–60% for production deployment.

<a href="https://toolmasterapp.in/word-counter" class="text-primary font-medium hover:underline" rel="noopener noreferrer">Word Counter</a> — Count words, characters, sentences, and paragraphs. Shows reading time estimate and keyword frequency.

<a href="https://toolmasterapp.in/lorem-ipsum" class="text-primary font-medium hover:underline" rel="noopener noreferrer">Lorem Ipsum Generator</a> — Generate placeholder text for mockups. Configurable word count, paragraph count, and format (plain text or HTML).

<a href="https://toolmasterapp.in/case-converter" class="text-primary font-medium hover:underline" rel="noopener noreferrer">Case Converter</a> — Convert text between camelCase, snake_case, kebab-case, PascalCase, and more — useful for renaming variables across codebases.

<a href="https://toolmasterapp.in/diff-checker" class="text-primary font-medium hover:underline" rel="noopener noreferrer">Diff Checker</a> — Compare two text blocks side-by-side with highlighted differences. Useful for reviewing code changes without Git.