How to tell whether an online tool is uploading your files
, 4 min read
Most free online converters work by uploading your file, processing it on a server and sending the result back. That is not inherently sinister, but it does mean your bank statement or Aadhaar scan sits on a company's disk, governed by a policy you did not read.
Checking for yourself
- Open the site and press F12 to open developer tools, then choose the Network tab.
- Run the tool on a file.
- Look for an outgoing request of roughly your file's size, usually a POST or PUT. If you see one, your file was uploaded.
A simpler version: load the page, turn on airplane mode or disconnect the network, then use the tool. Anything that keeps working is processing locally.
What a good policy says
Vague promises are common: "your files are safe with us", "deleted automatically". Look instead for specifics. How long are files kept? Who can access them? Are they used to train anything? A policy that cannot answer those is not really a policy.
Warning signs
- Tools that require an account for a one off conversion.
- Sites offering to remove a PDF password you do not know, which is either dishonest or worse.
- Download buttons surrounded by identical looking ad buttons.
- No contact address, no company details, no privacy page.
Habits worth keeping regardless
Strip location data from photos before posting them with Remove EXIF. Encrypt genuinely sensitive files before emailing them with Encrypt File. And when you download something important, compare its checksum with the one the publisher lists using File Checksum.