When you merge a PDF or scan a document online, you are often sharing something personal: an ID card, a bank statement, a contract or a medical report. It is reasonable to ask whether that is safe. The answer depends on how the tool works. This guide explains the difference and gives you a checklist you can use with any website.
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Try the browser-based scanner →Upload-based tools send your file to a company server, process it there, and let you download the result. Your document is copied to a machine you do not control. A good service deletes it after a short time, but you have to trust its promise.
Browser-based tools do the work inside your own device. The website only delivers the program, and your file never leaves your phone or computer. MZScan works this way for scanning, converting, merging, compressing and editing.
Documents such as ID cards, bank statements and tax papers deserve the strongest protection. Prefer browser-based tools, share them only with the organisation that needs them, and mark copies with the purpose and the date, as explained in our guide to making an ID card copy.
No website can protect a file after you share it. If you send a PDF by email or a chat app, the receiver controls the copy. Public computers are also a risk: if you must use one, close the tab afterwards, clear the downloads and sign out of your accounts.
Files can carry more information than you see. Photos often store the date, the phone model and sometimes the GPS location where they were taken. PDFs can include the author name and the software that created them. Before you share a file publicly, consider whether this hidden data matters. Re-exporting a page as a fresh image, or creating a new PDF from images, usually removes most of it.
Some websites imitate popular tools to trick people. Warning signs include pop-ups that tell you to install an extension to continue, a "download" button that gives you a program instead of your file, requests for card details for a simple conversion, and misspelled domain names. If anything feels wrong, close the tab and use a site you know.
Scanning, image-to-PDF, PDF-to-image, compression, PDF tools, ID tools and the text editor all run inside your browser. Only the OCR language data and fonts for the editor are downloaded from the web. You can read the details on our Privacy Policy page.
Is a browser-based tool always safe?
It is much safer for your documents, because the file stays on your device. You should still use trusted sites and keep your browser updated.
Do you keep copies of my files?
No. Your files are processed locally and are not uploaded to our servers.
What about my account?
An account is optional and is only used for Premium. It stores your email and plan details, not your documents.
Your files stay on your device. Nothing is uploaded.
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