How to Check If an Online JSON Formatter Uploads Your Data (opens in new tab)

Most developers have done this at least once. You get a messy API response. You need to inspect a JWT. You have a webhook payload, a log object, or a config file that is hard to read. So you open a JSON formatter, paste the content, and move on. That habit is convenient. But it also deserves a second look. Not every JSON tool behaves the same way. Some tools process your input entirely in the browser. Some send content to a server. Some store snippets for sharing. Some extensions have permiss...