Frequently asked questions

A tool that protects files with a password. The encryption runs in your browser, with no installation and no account. You choose a file, set a password and download the protected result.

No. The file you protect is not sent to a server. You can verify this yourself in the network tab of your browser's developer tools: nothing is requested beyond the website itself.

A modern browser runs program code directly on your device. Loclavis uses the browser's file APIs to read your selected file in sections, encrypts each section with the built in Web Crypto interface, and writes the result back out locally. No server connection is involved in that sequence.

File processing does, once the page has loaded. We measured it: load the page, switch the network off, protect a file and decrypt it again works completely. What does not work is reloading the page without a connection. Loclavis is not an installed offline app.

All of them. Loclavis works at the byte level and knows no format boundaries: PDF, Word, Excel, PowerPoint, images, archives, XML, CSV, video, audio and anything else. PDF takes a special route, because a directly openable password PDF can be produced from it.

What you get when a file is not an ordinary PDF. It holds your encrypted contents and the encrypted original filename. It stays encrypted until it is opened again with the right password.

It is the file extension of the protected Loclavis file. There is nothing more to it: a name so your operating system can recognise the file. You do not need to know anything about the format to use it.

They open loclavis.com/en/decrypt-file, select the protected file there and enter the password you gave them separately. Decryption then runs locally in their browser.

No. A current browser is enough. No account, no sign up and no software are needed, and decrypting is free.

Because that is easiest for the recipient. They open a password protected PDF in the PDF reader they already have and type the password. They do not need Loclavis for it.

Yes. You can always type your own password, and Loclavis never replaces it on its own. A password protected PDF does carry a higher minimum requirement, because a PDF protects its password less strongly than a protected Loclavis file: at least 12 characters and at least three of the four character kinds out of lower case, upper case, digits and symbols. If your password is still too weak for that, Loclavis says so and you can simply extend it.

No. The generator is there for anyone who would rather not invent a password. Your own password is just as valid, as long as it meets the requirements.

Because the file format itself has no notion of a password. For Word, Excel, images, archives and everything else there is no widely supported way to put a password inside the file, so Loclavis encrypts the file as a whole.

PDF/A is an archival format with structural requirements that later encryption can damage. Loclavis detects such documents and stores them unchanged inside a protected file. The original is preserved byte for byte.

The same. In ZUGFeRD and Factur-X an XML invoice is embedded inside the PDF, and later encryption can render that structure unusable. Loclavis detects it and protects the file unchanged inside a container.

Yes. They are saved as a protected Loclavis file. Loclavis does not set an Office password inside the document; it encrypts the whole file.

Yes, with Loclavis Plus. Folders are bundled locally into a single protected container; subfolders and filenames are preserved and encrypted. Decrypting gives you a ZIP archive with the original structure.

Yes. A folder with two hundred files counts exactly once, because you pressed Protect once. Folders are a Plus feature, though.

Yes. A ZIP you created yourself is an ordinary single file as far as Loclavis is concerned, and counts as one protect operation on the free tier.

Yes. Decrypting creates the original as a separate new file. The protected file stays where it is until you delete it yourself.

No. Loclavis does not know your password. It is only processed in your browser, never transmitted and never stored. There is no back door and no emergency key.

The file stays encrypted and cannot be opened again, not even by us. That is exactly what makes the encryption effective. So note the password down safely, separate from the protected file.

The password is created directly in your browser, from the browser's cryptographic random source. Every generation draws fresh random values. The password is not sent to Loclavis and not stored, and Loclavis cannot recover it later. Technically: crypto.getRandomValues, with rejection sampling so that no character is favoured.

Arithmetically yes, practically no. The standard password carries around 120 bits of randomness. Preventing a repeat would mean storing every password ever generated, which would be considerably worse than the problem it solves.

No. It appears in the input field and nowhere else. No local storage, no history, no log file, no transmission. Copying, saving as a text file or printing only happens when you ask for it.

Separately. Send the protected file by email or through a file service, and pass the password along another route such as a phone call, a text message or a messenger. If both travel in the same channel, the protection does not help much.

Yes, always and without limit. Even when your monthly allowance is used up or a Plus subscription ends. There is no paywall in front of your own files.

Using it at no cost: all file types, your own password, a secure generator, local processing and 10 protect operations per calendar month. Decryption is not capped. No sign up is required.

A yearly subscription at 5.99 euro. It lifts the monthly limit and unlocks several files in one operation, whole folders and additional password options.

No. Both use the same scheme with the same parameters: AES-256-GCM with Argon2id. Plus sells convenience and unlimited use, not better security.

Locally in your browser. There is no server side count, no IP analysis and no device recognition. Clearing your browser data resets the counter. We accept that, because the alternative would mean collecting data about you.

At purchase you are redirected to Stripe and enter your payment details there; we never see them. During a later licence check Loclavis sends only your Plus key to our verification function, and that key contains a Stripe subscription identifier and nothing else.

None. No files, file contents, filenames, passwords, derived keys or protected containers are transmitted. Payment and licence checking are entirely separate from this and touch no file.

Current versions of Chrome, Edge, Firefox and Safari. In Chrome and Edge you can pick the save location directly, in other browsers the result arrives as an ordinary download.

Single files are processed in sections and are therefore not artificially capped. The real limit comes from your browser and your memory. A folder container holds up to 65,535 files and just under 4 GB.

AES-256-GCM for the contents, Argon2id to derive a key from your password, and HKDF-SHA-256 to separate the individual keys. The password PDF uses AES-256 as defined by the PDF standard.

No. There is no seal and no external certification. What the application does is described on the security page, including its limits.

Your theme choice, the counter of this month's protect operations, the number of successful protect downloads used by the donation prompt and, if you have one, your Plus key with the result of the last check. No files, no passwords, no keys from documents.