Can I use Elba on a plane?

Yes. Elba works fully offline once the HTML file is on disk.

Do I need to install anything?

No. Double-click the HTML file (or open it via the included launcher) and it runs.

Is the source auditable?

The whole program is inside the HTML file. You can open it in any text editor and read it.

Guides/Offline HTML

Offline file encryption in a single HTML file

Offline file encryption in an HTML file sounds like a contradiction — until you remember your browser is a fully capable local runtime. Elba is a single .html document that, when opened offline, encrypts and decrypts a folder on your machine.

Why HTML, of all things

Because it is the most portable executable format on earth. Every operating system in current use can read one. No signing, no store, no compatibility layer.

You can copy Elba to a USB stick, email it to yourself, print it out if you want. It will still be Elba in ten years.

Airplane mode is a first-class use case

Elba was designed to be used with the network cable pulled. Journalists, lawyers, and travellers use it exactly that way. It has no ‘could not connect’ error state because it never tries to connect.

Questions people actually ask

Can I use Elba on a plane?: Yes. Elba works fully offline once the HTML file is on disk.
Do I need to install anything?: No. Double-click the HTML file (or open it via the included launcher) and it runs.
Is the source auditable?: The whole program is inside the HTML file. You can open it in any text editor and read it.

Take the island

Elba is one HTML file. It runs locally in a Chromium browser, seals a folder with AES-256-GCM, never phones home, and becomes open source on 1 January 2030.

€49MMXXVI· now ·
€39MMXXVII2027
€29MMXXVIII2028
€19MMXXIX2029
FreeMMXXX2030

the price falls each year · free to all 1 jan 2030

Take the island — €49

pay once · no account · nothing leaves

Related guides

Single-HTML-file encryption: why one file is the feature
One HTML file, one folder, one password. Why Elba's single-file design is a security property, not a limitation.
How to encrypt files on a Chromebook (properly)
Chromebooks don't ship with a real file encryption tool. Elba is a single HTML file that adds one, using the browser you already have.
An encryption tool for sensitive documents that fits on a USB stick
Contracts, medical notes, client files. A small, offline encryption tool for sensitive documents — one HTML file, one password.