Developer tools

Design realistic API responses without a backend. Features custom status codes, header kits, latency simulation, and instant JSON generation for frontend developers.

Encode and decode Base64 safely in your browser. Convert text to Base64 (and back), learn about UTF‑8, URL‑safe Base64, padding, and build data URIs for images or inline assets.

Transform your source code into stunning, professional screenshots. Choose from multiple editor themes, vibrant gradients, and macOS-style frames. Perfect for Twitter, LinkedIn, and blogs.

Create and test cron expressions visually. Generate human-readable schedules, preview upcoming run times, and use presets for Linux crontab and automation workflows.

Free difference checker to compare two texts online. Our text comparison tool highlights additions and deletions, making it easy to spot changes between file versions, code, or documents.

Effortlessly convert your HTML code into clean, readable Markdown with our free online tool. Perfect for developers, writers, and content managers.

Convert CSS to LESS with intelligent preprocessing, variable extraction, nested rule optimization, and comprehensive mixin support. Perfect for modernizing legacy CSS and improving maintainability.

Scan your website headers for security vulnerabilities, caching efficiency, and information leakage. Get a professional grade (A+ to F) and actionable advice to harden your server.

Convert JSON data to XML, CSV, TSV, and YAML formats with customizable options.

Compress JSON files by removing unnecessary whitespace and formatting. Perfect for optimizing file sizes for production and faster data transmission.

Format and beautify JSON data with customizable indentation. Perfect for making complex JSON structures readable and well-organized.

Convert JavaScript objects, arrays, and values to JSON strings with custom formatting, filtering, and indentation options.

Highlight JSON syntax with color-coded display for better readability and debugging. Features dark/light themes, copy functionality, and error detection.

Convert JSON objects to strings with options to preserve or escape special characters. Perfect for developers working with APIs, configuration files, and data serialization.

Validate JSON syntax, escape/unescape special characters, and analyze JSON structure with detailed statistics and error reporting.

Paste a token to instantly decode header and payload, verify signatures against secrets, PEM/JWK, or JWKS URL, validate claims, and re‑encode tokens for testing. Supports HS256, RS256, ES256, PS256, and EdDSA.

Create clean, aligned Markdown tables visually. Features spreadsheet-like editing, CSV/JSON imports, and instant export to Markdown, HTML, and CSV for GitHub and documentation.

Test any API endpoint directly from your browser. Our free online API tester lets you make GET, POST, PUT, PATCH, and DELETE requests, customize headers, and view raw responses instantly. Perfect for developers and testers.

Generate random binary numbers with custom bit lengths, patterns, and multiple output formats. Perfect for programming, computer science, and digital electronics applications.

Generate random CSV data with custom columns, data types, and export options. Create test data, sample datasets, and structured information for analysis and development.

Generate random dates with custom ranges, formats, and filtering options. Perfect for testing date-based applications, creating sample data, and scheduling scenarios.

Generate random JSON data from schemas with our advanced tool. Create structured data, arrays, objects, and validate your JSON schemas. Perfect for testing and development.

Generate random times with custom ranges, formats, and filtering options. Perfect for scheduling, testing time-based applications, and creating sample timestamps.

Generate random TSV data with custom columns and data types. Create structured tab-separated files perfect for data analysis, spreadsheet applications, and simple data exchange.

Generate random XML data with our flexible template system. Create structured XML documents, handle arrays, and export formatted XML files. Perfect for testing and development.

Generate random YAML data with our flexible template system. Create structured configuration files, handle arrays and objects, and export formatted YAML files. Perfect for testing and development.

Build, test, and debug regular expressions in real-time. Features live match highlighting, capture group visualization, and a comprehensive pattern library for JavaScript, Python, and more.

Transform JSON instantly into TypeScript interfaces, Zod schemas, JSON Schema, or GraphQL types. Features recursive type inference and professional customization options.

Format and beautify SQL queries with intelligent indentation, syntax highlighting, keyword capitalization, and comprehensive database support. Perfect for database development, code reviews, and documentation.

Explore, test, and debug Model Context Protocol (MCP) servers with our advanced GUI. Discover available tools, execute methods with custom JSON arguments, and monitor real-time logs.

Parse and analyze URLs to extract components.

Analyze and view detailed information about your browser's user agent string, including browser type, version, operating system, and device information.

Generate universally unique identifiers (UUIDs), also known as globally unique identifiers (GUIDs), using different standard versions. This tool is essential for creating unique IDs for database records, entities, and distributed systems.