Encrypted in this tab AES-256-GCM · WebCrypto

Cloak anything.
Reveal nothing.

CloakDrop encrypts your files in this tab with AES-256-GCM. The key is generated here, stays here, and rides inside the link — never on a server. Today it encrypts and stores; it does not yet send. A link opens only in the browser that made it.

A CloakDrop link is plain text, so it survives any channel you already use

Not yet, though: in this build a link only opens in the browser that made it. Sending one to someone else shows them an empty page. The relay that will carry drops between devices is being built — what works today.

Encrypt · Chunk · Seal

Under the cloak

Real AES-256 encryption, no accounts, and links that stop opening when you say.

Cloaked inside your browser

AES-256-GCM runs in your tab, chunk by chunk. Filenames are encrypted too, inside the manifest — plaintext never leaves this tab.

The key rides in the link

It lives after the # — the URL fragment. Browsers never send fragments to servers, proxies, or logs.

Every file type welcome

Documents, photos, footage, archives — the cloak doesn't care what's inside. A link stops opening after the time you pick — an hour, a day or a week.

We couldn't look if we wanted to

No accounts, no tracking, no data on our side at all — no file, no filename and no key ever leaves this tab. Wrong key, no files: cryptography keeps the promise, not a privacy policy.

Security, spelled out

No trust required. Verify it.

Every claim on this page maps to a mechanism you can inspect in your browser's dev tools. Nothing is hidden — except your files.

Cipher

AES-256-GCM via the WebCrypto API

Hardware-accelerated, authenticated encryption — the same primitive password managers rely on.

Key handling

Generated locally, never transmitted

The key travels only inside the URL fragment (#…), which browsers keep client-side by specification.

Chunking

4 MB chunks, unique IV per chunk

An 8-byte random prefix plus a counter guarantees no IV ever repeats under the same key.

Metadata

Filenames encrypted inside the manifest

The stored record holds ciphertext, sizes, and a timestamp. Nothing readable — and in this build that record never leaves your browser.

Integrity

Tampering fails loudly

GCM authentication rejects any modified byte — a wrong key or altered ciphertext yields no output at all.

Limits

Where the edges are

These are the limits this build runs under. All of them are in the code on this page.

Every drop
Up to 500 MB per drop
Links open for up to 7 days
As many drops as this browser has room for
No accounts, anywhere
Start dropping

FAQ

Fair questions

Is the encryption real?
Yes. The key is generated by your browser through crypto.subtle and never transmitted. Open your dev tools' network tab while you cloak a drop — you will see no request at all, because this build has no relay to send to. The key exists only in your link's fragment.
Is there a server?
Not in this build. Nothing is uploaded; the encrypted chunks go into this browser's IndexedDB and stay there. The relay being built will hold encrypted blobs, their sizes, and a creation timestamp — no filenames, no content, no key.
What happens if I lose the link?
The files are gone. That is what zero knowledge means here: there is no recovery, because we hold nothing that could recover them. Treat the link like the files themselves.
How long does a link keep opening?
As long as you chose before cloaking — an hour, a day, or seven days. Transfers are handovers, not archives, so there is no option to keep one forever. The age is checked every time a link is opened; in this build that clock runs in your browser, against the drop's creation timestamp. Deleting a drop is separate and immediate: it removes the encrypted pieces, so the link cannot open again at all.
Can I read the code?
All of it, right now — press Ctrl+U. The whole client is one unminified file, because a crypto product that says trust me instead of read it yourself is asking the wrong thing of you. It is not licensed for redistribution, but reading and checking it needs no licence.