Zero-knowledge, demonstrated

Ciphre encrypts on your device.
Our servers only ever hold ciphertext.

Type a note or pick a file below. It's encrypted in this browser before anything is "sent" — then you'll see exactly what your plaintext looks like versus the only thing Ciphre's database and storage ever receive.

What you see

On your phone or laptop — after decrypting with your key

Name
—
Contents
Press “Encrypt & send” to see it.

What Ciphre's servers would store

A representative encrypted record — generated here in your browser

original_name
—
content_type
—
enc_scheme
—
sha256 (content hash)
—
payload / stored bytes
—
The server has the ciphertext and the IV — plus routing metadata like size, timestamps and expiry — but never the key, so it cannot turn any of this back into your content.

Now decrypt it — as your other device would

Your other paired device holds the same key, so it can open what the server can't.

Key fingerprint (SHA-256) — the key itself is never shown or sent: —

This page runs the same cryptography Ciphre uses: a random master key on your device derives an AES-256-GCM transfer key (HKDF-SHA256, label ciphre-transfer-v1); your content is encrypted with it before upload. The key lives only in this browser tab — nothing here is sent to any server, and Ciphre's real servers receive only the ciphertext shown on the right.

Files up to 1 GB stream in encrypted 25 MB chunks so nothing is ever held whole in memory or seen in the clear. Public share links and guest drops are end-to-end encrypted too — a share link carries its decryption key only in the URL fragment, and a guest encrypts to your public key before upload.