Learn how to use our tools effectively. Tutorials, tips, and guides to help you work faster and smarter.
Learn what JSON Schema is, which drafts matter (4–2020-12), how SchemaStore helps, and how to use a free browser validator for APIs, configs, and package.json.
Free sample copyable QR code content: paste these URLs or text into a QR generator to get scannable codes. Includes sample QR code images for Spoold and the QR tool. Try in our free online QR generator.
Create a scannable QR code for your website or link in seconds. Free online QR code generator: website qr code, qr code to link, get qr code, test QR codes. No sign-up.
Copy the smallest valid PDF in hex or base64. Minimal valid pdf file bytes hex and base64 pdf for testing parsers, APIs, and viewers. Paste into our free PDF viewer to preview.
Discover how Magic Box instantly detects JSON, HTML, curl, JWT, CSV, regex, and 20+ formats. Learn how it adapts to your patterns and suggests workflows to accelerate your development.
Free online color picker with hex to RGB, RGB to hex, and HSL conversion. Pick colors with visual picker or eyedropper. WCAG contrast checker, shareable URL, palette export. No sign-up.
Create flowcharts and flow diagrams online by clicking to add nodes and dragging to connect. Auto-styling for database, API, user. Templates, export, share. No syntax—visual flowchart maker in the browser.
Learn what UUIDs are, when to use v4, v1, v7, or nil, and how to generate, validate, and export UUIDs with our free UUID Generator tool. Best practices and common pitfalls.
Format and beautify SQL online with our free SQL Formatter. Supports PostgreSQL, MySQL, SQLite, T-SQL, BigQuery, and 10+ dialects. Uppercase keywords, 2 or 4 space indent, copy, download, share. No install.
Edit Go, Rust, and Java online with Monaco syntax highlighting, format, and run (JS/Python). One editor for systems programming, microservices, and enterprise code. Free, no install.
Create flowcharts, sequence diagrams, class diagrams, ER diagrams, and Gantt charts with Mermaid syntax. Free online Mermaid editor with live preview, export to SVG/PNG, and GitHub-ready diagram-as-code. No design tools required.
Edit and run code in 40+ languages with Monaco (VS Code engine), syntax highlighting, format, and run JS/Python in the browser. Free, private, no install.
Write and run Python in the browser with our free online Python editor. Pyodide-powered execution, Monaco syntax highlighting, format on save, and share via link. No installation—ideal for learning, snippets, and quick algorithms.
Edit JavaScript and TypeScript in the browser with Monaco, syntax highlighting, and run support. No install—perfect for snippets, learning, and quick API or regex tests.
Master JSON formatting with our comprehensive guide. Learn best practices, common pitfalls, and how to use the JSON Formatter tool effectively.
Understand JWT structure, decode tokens safely, and inspect claims, expiry, and signatures. A complete guide with best practices and our free JWT Decoder tool.
Turn curl commands into JavaScript fetch or axios code in one click. Parse headers, body, and auth—with examples, fetch vs axios comparison, and best practices.
Test HTML, CSS, and JavaScript in the browser with no server. Live rendering, responsive preview, sandboxed iframe, and shareable links. Free online HTML preview tool for prototyping and debugging.
Convert CSV to JSON with auto-delimiter detection, table view, and export to JSON, SQL, or Markdown. Best practices, common pitfalls, and how to use the CSV Viewer tool.
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