Why "in your browser" matters
Most free document sites work the same way: you upload your tax return, your contract, or your ID to their server, they process it, and you download the result. The utility is real — and so is the copy of your document now sitting in someone else's infrastructure, governed by a privacy policy you didn't read. These tools take the other path: the processing code downloads to you, your document doesn't upload to anyone. Close the tab and nothing persists.
They're built by the team behind Paperlock, a private, Face ID-protected document vault for iPhone that reads your paperwork and answers questions about it. Same principle: your documents are yours.