You uploaded your passport to a website last week. I did too.
Think about the last time you used a free PDF converter. For most of us it was within the last week, and it took about ten seconds. Bank statement, ID scan, a signed contract. Drag, drop, download, done. In those ten seconds, your file left your computer. That's the part nobody thinks about. Online converters work by uploading your document to someone else's server and processing it there. Your…
When you recently converted a file using a free online PDF converter, that document likely left your device and traveled to an unfamiliar server. The service processes the file on their machine, which means your personal data could be stored on a server you don't control, possibly in an unfamiliar location. This practice has led to security issues in the past.
In July 2024, the cloud storage of two converter services was found to be publicly accessible, containing 89,062 files including passports, IDs, and contracts. In March 2025, the FBI warned about scam converter sites that may return your file with hidden malware and secretly scan files for sensitive information. Additionally, metadata hidden in files like photos and PDFs can reveal personal details like device IDs and GPS locations.
Experts advise against using online converters for sensitive documents. To avoid these risks, some have switched to using offline tools that run entirely on their own computer. This approach eliminates the risk of uploading sensitive data to an untrusted server. However, it's important to note that running software offline doesn't guarantee complete security if your own computer is compromised.
For those looking to maintain control over their files, tools like KinoFlux Editor offer an offline solution for common file conversion tasks.
Written by urgent.news from Dev.to's reporting — not their text. Machine-written — may contain errors; check the original before relying on it.