Carhartt, UK Airports Breached: Why You Should Verify 'Client-Side Only' Tool Claims

Carhartt suffered a data breach exposing 12.9 million customer records — including names, emails, and addresses — while Manchester Airports Group lost Wi-Fi signup data across three UK airports, both incidents linked to server-side data storage. These breaches highlight why users should scrutinize privacy claims made by web-based tools like JSON formatters and Base64 decoders that promise data never leaves the browser. Verifying such claims takes roughly 30 seconds: open the browser's DevTools Network tab, use the tool, and check whether any POST requests carry your input to an external server. Tools that genuinely process data client-side will show no such outbound payload, though third-party services like analytics may still make separate, unrelated requests. The core principle is straightforward — data that is never transmitted or stored cannot be exfiltrated, but users should confirm that for themselves rather than rely on footer disclaimers.