How much do you actually trust "Free Online Tools" with your data?

I was about to convert a sensitive contract using a free online PDF tool yesterday, and I froze. I realized I was about to upload a legal document to a random server I know nothing about.

I usually use generic tools for:

1. Removing backgrounds from images.

2. Validating JSON/Code.

3. Compressing files.

But I’m starting to feel like "Client-Side Only" (WASM) tools should be the standard for this stuff.

Question: Do you guys have a "No Fly List" for data? E.g., You'll upload a meme, but never a tax document? Or do you just trust the HTTPS lock icon?