JTC – JSON/YAML Type Checker Using TypeScript
Yet another JSON validator, but uses TypeScript types instead of JSON Schema.

Polished UI, but identical tools exist free on CyberChef, in VS Code, and browser DevTools.
Backend and frontend developers needing quick format conversions
CyberChef · VS Code extensions · Browser DevTools
Yet another JSON validator, but uses TypeScript types instead of JSON Schema.
Multi-language literal generator when quicktype already handles JSON-to-code conversion.
22x faster startup than jc with full parser compatibility and zero Python dependencies.
Everything important runs in the browser: JSON formatters, a JWT debugger explicitly marked 100% client-side, and a new Database Design Studio that turns SQL/Prisma schemas into draggable ER diagrams you can export as PNG. The product’s hook is convenience plus privacy — a single place to grab many small tools without sending snippets to a server. It’s useful and nicely designed, but the core idea is a well-curated bundle rather than a novel technical breakthrough.
Yet another CyberChef clone with 121 tools, but nothing you can't already do elsewhere.
Service-name DSL beats hand-maintaining Vercel Sandbox domain rules.