How I Built a React JSON Tool That Handles 150k+ Lines Without Freezing the Browser

Most JSON tools work fine… until they meet real-world production data. We’ve all been there: You paste a massive payload into a web-based formatter, and suddenly: The page stops responding. Scrolling becomes a stuttering mess. The "Page Unresponsive" popup appears. I encountered this while debugging complex automation flows and deeply nested configurations. I needed a tool that could handle 150k+ lines of JSON without falling apart, but I didn't want to compromise on privacy by sending that data