Free, private developer tools in the browser

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.