I got tired of ad-heavy JSON formatters so I built my own — here's what I learned

I use JSON formatters every day. Paste messy API response, get clean output. Simple. But every tool I used was either covered in ads, required signup, or sent my data to some server I knew nothing about. One day I was pasting an API key into one of these tools and stopped myself - why am I trusting a random website with this? So I built my own: getpdfmint.com/tools/json-formatter What it does differently Everything runs in the browser. No server, no logs, no account. You can paste API keys, internal configs, production data — nothing leaves your machine. It also tells you exactly where your JSON is broken. Not just "invalid JSON" - the exact line and character. Trailing comma on line 47? It'll find it. Auto-fix This is the part I'm most proud of. Most formatters tell you your JSON is broken and leave you to figure it out. Auto-fix actually tries to repair it - single quotes swapped to double quotes, unquoted keys wrapped, trailing commas stripped, missing brackets closed. One click and